After the last long track day without an oil cooler, I decided I wanted to actually know what was going on with temps.

https://cimg6.ibsrv.net/gimg/www.mia...c817364c4a.jpg
For now, the gauge is in a vent while I figure out how I want to bring it up onto the dash in a good looking manner.

Sometime in the spring, I began to notice a clicking sound from the driver rear corner when I got on and off throttle. I checked a lot of stuff at the back end, and never could find anything. I figured it was just axles, my poly bushings, sway bar links, something, but I never could find it. I checked all the hubs, and they were tight by my test. The car drove fine, so I began to ignore it.

Then I started to hear a grinding sound. I checked my hubs again. I changed out my tires. I checked my diff oil - clean and clear. I checked my driveshaft - it had a clear line of grease that escaped, so I figured that was it. I changed it out for a Dorman unit.

https://cimg1.ibsrv.net/gimg/www.mia...93c7a928fc.jpg
https://cimg2.ibsrv.net/gimg/www.mia...26ffed3bb2.jpg
https://cimg3.ibsrv.net/gimg/www.mia...e97c2b1dc4.jpg

No change in the noise, but I notice a vibration I've never felt before, but I'm paying a lot more attention now. Figuring it to be a crappy Dorman part, I return it and get an FM unit. Imagine my surprise when the FM unit comes it looking almost identical other than the part number, down to the weight placement. Same warranty sheet and everything, just $100 more expensive. I'm still chasing this vibration.

https://cimg0.ibsrv.net/gimg/www.mia...eea86ed507.jpg

The grinding sound started to get worse and became dramatic when turning left. I am losing my mind at this point. I start to take apart the poly bushings to check their health. Well, that's not good. I polished up all the sleeves on the rear suspension not related to alignment settings, cleaned out the bronze bushings with a bit of oil and a rag, and reinstalled with plenty of grease. I had been pretty zealous about greasing these at first, so I am disappointed by what happened here. When I installed these I sealed the bronze sleeve to the poly bushing with silicone, and I wish I hadn't. It's probably better to have grease go around the sleeve and clear out any dirt and water.

Eventually I realize it simply has to be the hub, so this time I really, really shove it around to check. And there it is, a small, hard to feel click. Only by violently shaking the car with the wheels on the ground, with the car on a very specific sideways grade, am I able to get a click. At home, using a lot of strength, I'm finally able to replicate it in the air.

https://cimg6.ibsrv.net/gimg/www.mia...efcb866e87.jpg

That'll do it.

A new Brofab Yaris hub went in on the drivers side. I didn't realize the new version used the normal 0.579" 1.8 rear stud instead of the smaller 0.507' knurl front studs used on the MR2 units. That caused an additional delay waiting for more parts. I torqued the bearings to Bronson's revised 250lbft torque spec. I've learned it's possible to stretch the axle enough with sticky tires to remove preload from the bearing. I'll be doing torque checks on these as a regular maintenance item in the future.

https://cimg4.ibsrv.net/gimg/www.mia...7f8bb394c4.jpg
The front Brofab hubs have been trucking along fine, but I've always been bothered by the spacer being free to move around without the wheel torqued down. I noticed this threaded hole was centered between the two lugs, so I had a slot cut in the hub spacer in order to use a button head screw to hold it down.

https://cimg5.ibsrv.net/gimg/www.mia...cfca52caaf.jpg

No more worries about dirt and brake dust ingress when working on the brakes!

I've also had a string of CELs of late related to cat performance. First the downstream o2 heater went bad, then I replaced it. For that, I got a P0420 cat effectiveness code. And when I was troubleshooting the driveshaft, I knocked the sensor around too much and broke it.
https://cimg5.ibsrv.net/gimg/www.mia...8a54c47864.jpg


Not being satisfied with the crusty state of the stock Michigan native take off exhaust I replaced after my last P0420, I went for the pricey option and got an FM 2.25" mid pipe. It took me a while to find the right adjustment for everything, but fit and clearance are now excellent. It's a tiny bit louder, but the tone is much the same as stock. I'm happy with the change, but sort of wishing I'd gone for the 2.5" option to give a bit of room for any future power increase.

https://cimg7.ibsrv.net/gimg/www.mia...9958c74918.jpg
For the past few years the carpet has been coming untucked on the sides of the footwells. That's due to the tabs that hook over the sills missing on my carpet, and that I've removed lots of the jute insulation after water damage.

https://cimg8.ibsrv.net/gimg/www.mia...183fc40155.jpg
I bought the cheapest foam sleeping pad I could find and cut it to fit around my footwells.

https://cimg9.ibsrv.net/gimg/www.mia...840302f1e8.jpg
I slipped it under the carpet and no more gaps! The footwells are a bit cooler as well.

Are you running stock ECU? Megasquirt? I, like you, want gauges for all the things - but it's kind of impractical I'm realizing. I like the digital dash that @BEAVIS runs: .

It would be nice to have the option to see everything.

Stock ECU unfortunately. I had a bad experience with Megasquirt and decided I preferred unquestionable reliability over a bit more power. The next step was going to be installing an MP62, but I obviously never got around to it. Now I'm itching for more power again and have been spending a lot of time pondering over various swaps and power adders.

Another few small projects I haven't added to the thread.

https://cimg5.ibsrv.net/gimg/www.mia...5c5e897879.jpg

The Speedway cable adjuster came with an ugly yellow sticker to denote which direction to turn for more front/rear bias. I didn't want that yellow and purple combo in my car, so I had my buddy make me this instead.


https://cimg7.ibsrv.net/gimg/www.mia...1292d0566d.jpg

I attempted to turn it black with some kind of gunsmithing touch up product. It came out looking like ass and pitted the surface pretty badly, and the finish was not durable at all.

https://cimg4.ibsrv.net/gimg/www.mia...3ca442a589.jpg

I sanded it back down to metal and painted each half a different color.

https://cimg6.ibsrv.net/gimg/www.mia...000ad4a124.jpg

The finished product in the car. I had wanted something a bit less eye catching than turned aluminum, but I'm happy with how it turned out.


I've been chasing vibrations for a while now. I caught a glimpse of the motor mount and thought replacing this driver side mount might fix it.

https://cimg9.ibsrv.net/gimg/www.mia...440047fa25.jpg

https://cimg1.ibsrv.net/gimg/www.mia...6f6bd8a83d.jpg

The vibration was still there with a hybrid Innovative and Mazdacomp mount pairing, so I tried just the rubber Mazdacomps. It's still there. I'm thinking it's the new FM driveshaft that's at fault. Thankfully I kept the original driveshaft and will swap it back in to see if anything changes.

Once the vibration is gone, I'll go back to the hybrid setup with the passenger side Innovative mount. It seems like a great combination of Cadillac vibration isolation and holding the motor decently in place.

So, why all the extra effort on getting the brake proportioning valve be cab adjustable when it's set to full rear and still locking up? Well, partially for racecar bling. But also...

I have plans. Complete overkill plans.

https://cimg7.ibsrv.net/gimg/www.mia...c4aa624aba.jpg

Afco F88 brake calipers were STUPID cheap this spring. I paid $45 for this forged body, 4 staggered diameter piston piece of amateur level NASCAR caliper. If it can stop a 3,000lb V8 monster, it can stop my Miata. This is the 0.81" rotor version.


https://cimg6.ibsrv.net/gimg/www.mia...acc8142b75.png

Here's a first draft of the rotor bracket. I'll probably add a bit more beef in the middle of the bridge, but the plan is to do a Supermiata style double sheer "Boxmount" setup so it should have much more effective reinforcement than additional thickness on one side. Patents can't stop you if it's not for resale!

https://cimg9.ibsrv.net/gimg/www.mia...3721315a88.png

For the rotor hat, I experimented with some lightweighting but it's just going to be a full beef setup, slightly thicker than the stock rotor hat. So I'll have the equivalent of about 1.3mm of spacer if I remember correctly.

https://cimg7.ibsrv.net/gimg/www.mia...d2fe7f205d.jpg
Getting the caliper positioned properly took more clearancing of the caliper and upright than some other setups I've seen online
https://cimg8.ibsrv.net/gimg/www.mia...808c82c990.jpg
An earlier version of the hat was 3d printed for test fitting.
https://cimg5.ibsrv.net/gimg/www.mia...2bbf57b6b7.jpg
Plenty of ventilation!

This 11.75" brake setup should actually shift my bias rearward by about 15% if my calculations are correct. That's roughly equivalent to running Sport rear brakes and 1.8 front, which I've seen a lot of people say is a well balanced setup that actually allows the rears to lock up first with no prop valve.

Then, once I get a few other home projects done, I can start thinking about adding some real power.

Actually, article 28 of the TRIPS act covers replication in any form. We spent a lot of money obtaining this patent, its provisions and protections. It matters.

Smart to use the solid hat. The printed shape does not look like it would hold up in our experience.

That is an aspect of US patent law that I had been mislead on. Noted.

The printed hat shown is for test fitting only. Cutaways are simply to speed printing time and reduce material usage.

Progress is slow on the BBK, but I now have access to a more local 3d printer to test fit on my car, and not just random junkyard parts of unknown provenance and straightness I left with my guy. Plus now I'm the one doing the CAD instead of just pen and paper drawings and begging him to turn them into stl files.

With the parts actually test fit on my car, I did a bit of fine tuning to get the rotor centered and the pad edge aligned with the rotor edge. Should just be one more test print on the bracket, but hats are in line for machining.

https://cimg4.ibsrv.net/gimg/www.mia...4af231bbbe.jpg
V2 of the hat, but the first one I've got on site.

https://cimg0.ibsrv.net/gimg/www.mia...cd45d5a915.jpg

I've got loads of clearance to the spokes, and radially it clears wheel weights on the inner wheel barrel by about 3mm on this 15x8 +25 Hexaform. These tires are shagged, I'll swap over my street tires to these wheels, ditch the old Hypergrams, and upgrade the track set to 15x9. I am not one to swap wheels constantly but the Hypergrams were simply a decent choice at the time, not my aesthetic preference.

https://cimg0.ibsrv.net/gimg/www.mia...50dfa2ef05.jpg
I'm only losing about 0.05" of clearance between the tie rod and the inner rotor face.

https://cimg2.ibsrv.net/gimg/www.mia...d73e16ba49.jpg
Bracket without the rotor.


Also, turns out that the cheapest rotors on Speedway are hilariously poorly cast. Check out this wobble in the vents. I might need to consider an upgrade.

i.imgur.com/6Fir0I6.mp4

Fun to watch this come together. Awesome you were able to fit it under a 15x8. Perks of the narrow friction ring! I kinda like the yellow hat.

Doing this on my own has really made me appreciate how well thought out your 1175 kit is. You guys did great work on it, especially with the duct setup. I've seen a few others post CAD pictures of ducts that go between the caliper and upright, but none that have an actual finished product.

Appreciate that. Ultimately that's why we decided to do the whole AFCO thing, which I know you weren't crazy about and I get that too. But having it all PNP ready to go makes it much more accessible for folks that don't have your skills or resources.

Still love seeing good old fashioned DIY ingenuity. :likecat:

Christmas came early this year. Look what finally came in!

https://cimg3.ibsrv.net/gimg/www.mia...0207a009a9.jpg

Nickel plated for corrosion resistance and swag, helicoiled for strength.

https://cimg4.ibsrv.net/gimg/www.mia...1a1006bd02.jpg
Oops, fingerprints.

https://cimg2.ibsrv.net/gimg/www.mia...21a0640851.jpg

They test fit great, the rotor is perfectly centered which worried me.

https://cimg5.ibsrv.net/gimg/www.mia...03f8ca4c18.jpg

To top it all off, I grabbed a set of 15x9" Flyin Miata Kogekis.


https://cimg6.ibsrv.net/gimg/www.mia...6f46189f8a.jpg

I call them Konigekis - FM says in all their info that they can't disclose the manufacturer, but right on the box there's a Konig sticker. That's not very secretive.

I'll be putting these on after the holiday. I need to swap over my street tires to the Hexaforms before I can drive with them on the street.

On Saturday I got the brakes installed. Today, I went into the mountains without looking at the forecast and found great weather for testing racing brakes.

https://cimg3.ibsrv.net/gimg/www.mia...bd3401c8c1.jpg

https://cimg5.ibsrv.net/gimg/www.mia...d81685b7c3.jpg'
https://cimg8.ibsrv.net/gimg/www.mia...61582aa9c9.jpg

I never drove this thing in the snow in 6 years in Michigan. I didn't expect to do it here in North Carolina, but as long as there's not salt on the roads I'm game.

I may be biased towards orange things but damn those nickel plated pieces are totally gorgeous.

What's that sitting on your work bench behind the assembled bits? some sort of transmission thing? Looks as though it could be motorcycle related....

The nickel plate turned out ridiculously well for being done in a home kitchen. I was debating nickel plate or anodizing, and I'm so happy with my decision.

As for the other background project, it's actually for my Jeep. That's an NP242 HD, it's a full time 4wd transfer case that's something of a rarity out of a V8 Jeep Grand Cherokee. It's actually pretty close to the same transfer case that came in a Humvee. I plan to make it work in my XJ behind a manual transmission. It's sorta like this Afco project - complete overkill for my needs, but fun to do anyways.

https://cimg9.ibsrv.net/gimg/www.mia...4435bc0076.png

On the Miata, the next thing I want to get done is have my hardtop painted. Over the summer I actually almost bought another hardtop, and went on a long drive to check this one out.

https://cimg6.ibsrv.net/gimg/www.mia...d4ef53ddfe.jpg

It was a new production example, painted the color I wanted, and for a decent price in todays market ($2,200). I found a few small blemishes and justified walking away by saying I would just get mine painted. That was stupid.

https://cimg8.ibsrv.net/gimg/www.mia...52881407f6.jpg

I guess doesn't bother everyone, this guy took his shot last week.

On a more serious note, I had to move on from my old wheels as they didn't clear the Afco brakes. At first I was thinking it was a bit of money wasted to spend money remounting tires, but now I have no regrets. Tonight, I glanced at the pile of them while working in the garage and something caught my eye.

https://cimg9.ibsrv.net/gimg/www.mia...9442e296f5.jpg

https://cimg0.ibsrv.net/gimg/www.mia...36dde34689.jpg

I had checked these wheels a few years ago for cracks, but focused on the spokes. They were soon retired them from track use to be just street wheels. The plan was to sell them to a friend, but now I am wondering if I should just send all of them to the scrap bin. I'd previously replaced one that was bent, I'm not sure I want my less experienced friend gambling on the life left in the other two I bought back in 2016.

CHECK. YOUR. WHEELS.

After buying some old track day pictures that were about to be taken down, I realize that I haven't shared many pictures of the car actually on track. Let's change that!

https://cimg2.ibsrv.net/gimg/www.mia...1d10826ef9.jpg

https://cimg3.ibsrv.net/gimg/www.mia...f0419933c5.jpg

https://cimg4.ibsrv.net/gimg/www.mia...3f8d029855.jpg

https://cimg6.ibsrv.net/gimg/www.mia...75bbcc1edd.jpg

https://cimg9.ibsrv.net/gimg/www.mia...72e6f45368.jpg


And a bit of a drift compilation.

Can't believe hardtops are going for that much, but I guess it is what it is. If mine got destroyed I don't think I'd be replacing it.

Nice drifting, and I agree. There is something great about camping out of your race car. Hoping I'll still be able to do that with mine this season.

Track season is fast approaching. I've got my first track day already booked at VIR for March 9-10, and have quite a few changes I want to make before then.

First and foremost, I have a persistent P0304 code for a cylinder 4 misfire. It only occurs during warmup at idle. I've been able to avoid any rough running or codes simply by not letting it idle during the warmup, I just get in and go, and remain stationary as little as possible. Once warm, it was fine. Idled well, and pulled with full power to redline. The other day it misfired at a hot idle as I was pulling into the garage and I knew I could ignore it no longer. Here's what I've done in the past few weeks.
.

1. Compression test - All cylinders at or above 180PSI both hot and cold. I tested this with the throttle closed for some reason.
2. Changed spark plugs for a new set of NGK BKR5E-11 plugs. No change.
3. Changed the 1/4 coil for a spare, including the insulator boot and spring. Swapped them between 1/4 and 2/3. No change. I have a few spares floating around from previous misfire adventures. None of them fixed this.

It's almost always a P0304 and not a general P0300. So it's got to be something specific about cylinder 4. If it was a coil issue, I'd expect a P0301 or P0300 for cylinder 1 or multiple misfires. I've tried three different coils and boots, and new spark plugs. It has good compression. Airflow should be the same to all cylinders, but I am taking that for granted right now.

At this point I felt like my best target was to check for fueling issues, so I decided to get the injectors cleaned. The car has 185,000 miles it, and has spent about 5 months every year for many of the last 8 years waiting for salt to go away. The injectors have earned a spa day.

https://cimg7.ibsrv.net/gimg/www.mia...022f62b3a5.jpg
Taking apart the intake manifold is pretty straightforward. I used some earplugs to fill the injector ports while it's apart.

https://cimg4.ibsrv.net/gimg/www.mia...f43f04ac14.jpg
The injectors looked fine to a visual inspection, and the plugs okay. One of the spacers tried to run away, I found it stuck between the manifold brace and the oil filter.

I shipped them out to Fuel Injector Clinic last week. Yesterday I got a call and was told that the initial flow test did indeed show that injector #4 was not flowing as much as the others and had some debris in the screen filter, but in their opinion it was not enough to cause a misfire. Hopefully their hunch is wrong.

The second engine issue I have is due to the Junk2 throttle body. Ever since it was installed, I am getting stalls as it returns to idle on warm up when it's below 40* out. I am convinced this is due to the terrible IACV passages. I believe they provide so much extra flow restriction that the ECU just isn't able to compensate for as well as it can with the stock TB.

https://cimg6.ibsrv.net/gimg/www.mia...3e9fd3d0ac.jpg

So with the manifold off and the car not running anyway, I went to town on opening up the most egregious offender to flow, the manifold side passage. As designed by Skunk2 it's an extremely thin passage full of 90* bends. I spent some time with a file and opened it up to the edge of the gasket, removing every sharp edge I could along the way. The surface got some collateral damage, but it'll seal up fine with a skin of silicone.

The stall issue existed pretty much from the first time I drove it in the cold, but I'm sure the misfire issue and the stall issue aren't helping each other. With the throttle barrel cracking issue other people have with the Junk2, I am going to give the stock TB the Supermiata recommended epoxy treatment to prep it for potential use. If this fixes the stalling, I'll keep the stock one in the track spares box. If it doesn't, this thing is coming back off.

The injectors came back from their spa trip yesterday, so I was able to get the car buttoned back up.

https://cimg0.ibsrv.net/gimg/www.mia...4e091b0298.jpg

I'm hoping there was improvement in the #4 injector not captured by the flow rate testing, such as spray pattern or a more dramatic difference at low flow rates. At least it's a directionally correct change.

https://cimg1.ibsrv.net/gimg/www.mia...bf482345f4.jpg

The injector seals to the head had certainly seen better days. Maybe there was a small air leak here that contributed?

https://cimg5.ibsrv.net/gimg/www.mia...69ab68219a.jpg

This two year old tube of anaerobic gasket maker was still usable, and it seemed better than opening a massive tube of RTV for such a small surface.

Of course, as per Skunk2 TB install SOP I loctite'd every bolt and nut involved.

https://cimg7.ibsrv.net/gimg/www.mia...3befe29097.jpg
It took a bit longer to get to this view than I expected.

While the rail was depressurized, I replaced the fuel filter to protect the new injectors. It was a lovely reminder about what a pleasure it is to be covered in gasoline. I also wanted to flush out the fuel rail. Unfortunately, even with every sensor plugged back in, the fuel pump wouldn't prime. I tried tapping and reseating the main relay in the engine bay, the fuel injection pump relay in the dash checking the ECU fuse in the dash, the fuel injection fuse in the engine bay, and jumping the F/P and GND pins in the engine bay diagnostic connector. No change.

Eventually I found a pinout to jump the under dash fuel pump relay and finally the pump kicked on. It moved enough to push gas out of all four injector holes. Call the fuel rail flushed.

Lastly I superglued the fuel rail spacers to the rail in order to prevent any further adventures into the engine bay abyss.

https://cimg9.ibsrv.net/gimg/www.mia...85f8b31bff.jpg

This is the sort of thing that bothers me. What should be a regular old 4 pin relay is some sort of special one only used on the Mazda Miata and Protege from 1997 to 2005. Rockauto has it for $14 but if I'm ever out on the road and another replacement relay fails on me, I'm looking at $75 to get a replacement on the road if I can even find one that day.

I am considering trying to repin the terminals into a more standard relay format. They look like they'll fit the standard 1" square brick style of relay.

Now is the time for me to reiterate - I really wish good factory manuals for Miatas were as reliable and easy to find as they are for my Jeep projects. It's frustrating having to google for forum info on electrical information, connector by connector.

https://cimg9.ibsrv.net/gimg/www.mia...d3d2be3fcc.jpg
The Fel-Pro gasket came out of the packaging warped and scratched. That's what I get for buying parts from Amazon.

I got it buttoned up too late to try starting. The garage is right below the master bedroom and I didn't want to wake the lady.

While the car was down for the injector cleanup, I chipped away at some other projects. Since I am still not sold on any route to more power, I need to make the most of what I have by cutting down on weight and drag.

I went across the scales at my local scrapyard some time back. After accounting for the weight of passengers and fuel, the car should weigh 2,430 lbs. She's a thick girl for a Miata.

I'm starting by removing whatever I can that won't really affect the driving experience.

https://cimg8.ibsrv.net/gimg/www.mia...83046ca9c5.jpg

These fog lights have been garbage from the get go. I think a previous owner may have used this as an RV dinghy or something, as the front end has been repainted with no signs of impact damage, and the glass surfaces are really rough. While I could replace them, removing them and installing a custom block off plate saves 1.5lbs total.

https://cimg9.ibsrv.net/gimg/www.mia...24d6daf69a.jpg

The manual steering idler pulley is a somewhat sought after part from my old 1.6 NA, but it's 3.5lbs that can be removed if I instead use a belt that only goes between the crank and AC compressor.

https://cimg5.ibsrv.net/gimg/www.mia...7b16f3e2de.jpg
To clean up the airflow a bit at the front end, I added an RS Factory knock off front lip and some RGR spats. I'm not sure if there's a measurable difference from the lip, so it also helps that it looks fantastic. I really like the NA R-Package feel it has.

I wish I'd have weighed it to keep the theme going.

https://cimg9.ibsrv.net/gimg/www.mia...7b4e23dd0b.jpg

Something I've noticed with newer cars is that the wheelwells have much more attention paid to them than the NB Miata, with its design roots in the '80s. In the front it's pretty decent, but in the rear the sill sticks out 3". Since I'm not Adrian Newey, I can't visualize this in my head, but I imagine air rotating with the tire is getting flung into that edge and redirected back into the wheelwell, under the car.

https://cimg2.ibsrv.net/gimg/www.mia...86950257d2.jpg

Compare that to the wheelwell on any new car you see, and it'll look something like this Chevy Volt - a smooth internal surface with a small spat or fence hanging below the body.

https://cimg0.ibsrv.net/gimg/www.mia...dbe8d7bffc.png

I did some rough mockup with a beer box...

https://cimg1.ibsrv.net/gimg/www.mia...713040fa7e.jpg

And took that template to Wal-Mart, where I found the cheapest plastic container I could as a materials donor.

Since the wheelwell has no place to attach anything, I had to make up some mounting tabs. They're just pieces of plastic held to the sheet metal with VHB foam tape.

https://cimg5.ibsrv.net/gimg/www.mia...dd1c3a029e.jpg
I didn't grab pictures on the rear sill, but I did a similar thing on the front to better support the back of the lip.

https://cimg2.ibsrv.net/gimg/www.mia...c182fb8a6f.jpg

After some trimming, the trash can was a nearly perfect sized source of plastic. The only issue is that it's polypropylene, which isn't the best choice of material. It's worth the $4 gamble though.

Like the cement mixer undertray, this is worth a cat!

Glad to hear someone doesn't think that project is a total waste of time! I am planning on more aero work like this in the near future, maybe cleaning up the rear of the underbody. I just can't do a wing.

Some little mods now, truly detail stuff.

https://cimg8.ibsrv.net/gimg/www.mia...80b439b69f.jpg
Last time I messed with my motor mounts I had a bad time, and felt the subframe was to blame. The driver side motor mount hole isn't slotted, but simply has two holes top and bottom. The passenger side is fully slotted. Hoping to ease the effort, I cut the drivers side out to match the passenger side. I've no idea why it was designed this way, but it was a lot easier to get the mount in place like this.

https://cimg0.ibsrv.net/gimg/www.mia...aee2a17435.jpg
One thing they changed from 93 to later years is this little slot in the trim panel at the rear of the door.
https://cimg9.ibsrv.net/gimg/www.mia...6eb8346293.jpg
Its purpose is to hold the belt buckle in place while no one is using it. On track this would fling into the roll bar if not carefully stowed. It's audible in some of my on-track videos, and I'm glad it won't be any more. I wish I had done this years ago.

I just stick my spare belt buckle into the receiver ...

great read - thanks for the entertainment

That doesn't work when you've pulled out the drivers seat and the receiver comes with it! Although now I wish I had made the hole somewhere more hidden instead of matching the stock location. There are surely nicer looking ways to do hold them still, but this required almost no thought.

__________________________________________________ ____________________________________________

This weekend is a double header track day at VIR hosted by the SCCA. I considered doing the Time Trial, but my mods like the fender spats, throttle body, Brofab bearings, and frame rail braces all push me into uncompetitive categories by my read of the rules. Would anyone care? I don't know, but I'd rather not deal with it. I can time myself and compare to the results everyone else gets.

When we left off, I had gotten the intake and fuel system back together and had a fuel pump relay failure. Turns out, this is a pretty common issue on the NB. Flyin' Miata sells both a higher rated relay, and the old Trackspeed relay kit. They're each $100 though! :eek:

Rather than deal with some limited production, hard to find relay, I wanted something readily available. So, I changed over to a generic Bosch style relay rated at 50 amps and powered it directly from the battery instead of through the Main Relay. This should improve the reliability of both relays, and be easier to fix if it's my fuel pump relay that goes bad on the road. I grabbed a spare main relay off of rockauto for $20 just in case, but with the highest load item removed from it's circuit, even a cheap replacement should be much more reliable.


https://cimg3.ibsrv.net/gimg/www.mia...a4e6257e03.jpg
Thankfully the terminals are standard blade style, making this an easy test fit and conversion.

https://cimg4.ibsrv.net/gimg/www.mia...3754a6689f.png
I hung the new relay in the stock location.

https://cimg6.ibsrv.net/gimg/www.mia...0d6b3ea9ac.png
Power wires went back along the drivers sill, across the gas tank tray...

https://cimg0.ibsrv.net/gimg/www.mia...bfc8b95bf1.jpg
... and to the battery. With two items now powered directly off the battery (the other being my 12v outlet), I feel like it's time to set up a fuse block back here when I get time.

https://cimg6.ibsrv.net/gimg/www.mia...5cf4093a6d.jpg
Continuing the weight reduction theme, I pulled 1.5 lbs of sound deadening off of the gas tank access panel while I had it removed.

https://cimg5.ibsrv.net/gimg/www.mia...fa71b6ad2c.jpg
To keep AC functional with the idler pulley removed, I found thread on Miataturbo about a stretch belt option that fits the pulleys well. The only downside is that it is a 3 rib belt, vs the 4 rib pulley. So far it's worked well, but the peak need for AC is many months away.

Do you like my Crocs?

https://cimg4.ibsrv.net/gimg/www.mia...3e47d7a6a6.jpg
I grabbed some cheap install tools off of Amazon to get it on there.

https://cimg2.ibsrv.net/gimg/www.mia...5e721ab2b2.jpg
The NB2 strut tower brace isn't a dainty thing. 3.25lbs for the center bar...

https://cimg6.ibsrv.net/gimg/www.mia...97fbc417c7.jpg
... and the towers weight 2.3lbs each. I still have the drivers side one in place due to the MC brace, but I am working on a lighter weight, more blingy setup.

https://cimg0.ibsrv.net/gimg/www.mia...550cb5534e.jpg
Speaking of weight reduction, I was surprised to do a side by side comparison and found the 11.75x0.81" to feel significantly lighter. Not only is the rotor overall thinner, it also has larger vents, so there's significantly less thermal mass. Looking at it now, it's hard to believe the stock rotor moves much air.

https://cimg8.ibsrv.net/gimg/www.mia...9bab1ff54a.jpg
I got it aligned earlier this week. The Paco stands seem to consistently under report camber (maybe due to the effective offset changing the suspension load?). I targeted 0.6* more than my end goal all around. Assuming that's true, I'm at 2.5F/2.0R camber, zero toe all around, max caster. Pretty close to the Supermiata Dual duty setup.

https://cimg4.ibsrv.net/gimg/www.mia...3a859a1c90.jpg
I gave the new 15x9 and 225 RS4s a test run on my Thursday commute. No scrapes or rubs thankfully, I still feel like I need to look into getting my fenders rolled.

Tonight I've got to throw as much stuff as I can in fit in the Jeep and get ready to camp at a rainy VIR. I'm starting to see the value of a larger tow vehicle and a full trailer. Most of my concern is due to the weather, and my as yet untested BBK. It is a bit nerve wracking knowing that you've truly taken your life in your own hands, so I am bringing the entire stock front brake setup as a backup.

The car is looking great. Also funny that you just did the same thing I did with the rotors, I was super surprised to find the huge ass 11.75 rotor setup to actually be less rotating mass than the OEM (sport) brakes. Good stuf. Also love the wheel spats, and the wheels look great too. Nice work all around.

VIR was total carnage this weekend - a cold and rainy Saturday had a lot of people crashing out.

225 RS4s definitely were not the ideal tire for the conditions, but I made it work. I did have an incident going too deep into T1, but thankfully I got it slowed down in time and wasn't in danger of hitting the wall. The tow truck almost had to pull me out though, there was just zero traction out there.

https://cimg9.ibsrv.net/gimg/www.mia...8430229e76.jpg
The guy next to me in the paddock lost it going into the uphill esses.

https://cimg0.ibsrv.net/gimg/www.mia...d28cbd74f4.jpg
This C6 Z06 hit the pit entry barrier and cut off the whole front corner. Driver was okay thankfully!

https://cimg2.ibsrv.net/gimg/www.mia...6416a19920.jpg
I've never seen an upright rip in two.

https://cimg4.ibsrv.net/gimg/www.mia...ffe5ef86f8.jpg
Sadly, I picked up some damage as well. The uhaul trailer hung up on my nice new low lip.

https://cimg3.ibsrv.net/gimg/www.mia...5b844d08b0.jpg
Some pretty iconic cars in grid.

https://cimg5.ibsrv.net/gimg/www.mia...d44d154640.jpg
This yellow RX7 was MOVING. It's great to see a car like this get to stretch its legs and not just be a car show ornament.

Thankfully on Sunday it did clear up, and I got some good sessions in. I was improving every session, making up time and steadily pushing deeper into the braking zones. There's still time on the table, especially with how I played it safe on the brakes on the back straight.

https://cimg8.ibsrv.net/gimg/www.mia...46bd6b6511.png

How's that for consistency? I could definitely feel the difference in grip on the last two laps. It was most obvious going into the right hander into Snake.

The car was sublime. Oil temperature peaked under 250. Coolant temps stayed under 210. The suspension ate up the curbs and asked for more. The only adjustment I made all weekend was to tire pressure. I did 32 PSI cold in the rain, and 26 PSI cold on Sunday.

The new brakes were fantastic! The pedal feel and balance was excellent. I had removed the in-dash bias adjuster cable as it just wasn't working, so I took my best stab at setting the brake proportioning valve and it was pretty spot on. I had three lockups big enough to scuff the surface - two on the front axle, and one big puff of tire smoke from a rear tire going into Oak Tree. The difference in feel of front vs rear lockup was pretty interesting. Trail braking gives me more rotation now too. I feel like there was a bit more piston knockback than I was used to with the stock brakes though. There was definitely more pedal travel before building pressure after the uphill esses, maybe due to spindle flex? My theory for this is that the stock sliding caliper can pivot slightly to deal with any spindle flex, while the solid mounted Afco can only deal with rotor misalignment by getting piston knockback.

Unfortunately, I did not have my gopro on me so no footage. But it was awesome! I should get some on-track pics in the coming days.

I'm still waiting on the professional pictures, but here's the best one my dad got.

https://cimg4.ibsrv.net/gimg/www.mia...cf019448ea.jpg



Anyway,

So turns out, my local yard is having a sale this weekend - $75 for all you can carry. There's a bunch of BMW E9x 3-Series in the yard, and as per my last post it's past time to get ABS in this car. I've read through Wingman's posts and picked his brain a bit. I'll be bringing in a bucket and hopefully leaving with the basis of my next major project, an Mk60 system. At first I was targeting the E5 system as he did, but I have some research to do to see if this car in particular can be a good donor. If it is, I'll probably grab it as well.

https://cimg4.ibsrv.net/gimg/www.mia...5ea869b5c8.jpg

Sadly, I don't think I can carry a V10 on my own. :'(

I just removed the strut braces off my car as well. I was surprised by how heavy they were. From my research, it sounds like they don't aid in handling, just in NVH. Not sure if that's true, but along with another brace I'm planning to pull I think it'll be worth 10-12 pounds.

Any plans to move over to a lightweight battery? Seems like a no brainer if you're looking to reduce weight.

I'm trying to stick to the free weight removal for now. Unfortunately, I've probably got more than 60 lbs in extra weight that I really do, and really don't want to remove - the soft top, and the hitch I so rarely use. I have plans to modify a lightweight trailer I've got to carry tools and tires, and it only took one top down drive after the worst winter weather had passed to remind me why I barely use the hard top in the nicer months.

A lightweight battery is definitely on my mind, but for now I don't plan on picking one up until my current one is done for. It's several years old at this point, and my system seems to overcharge the battery to 15.7 volts, but it still keeps on trucking. I should probably figure out that overcharge first, now that I think about it.

I pulled the NB2 Sport underbody brace (Factory butterfly) off my car as well. I haven't weighed it yet, which is why I haven't mentioned it.

Same boat here. I have a minimum class weight of 2330 (with driver I think?) and I'm pretty sure I know how to get there, but I like having the soft top, AC, etc... Seeing all of these clean, wide open engine bays makes me think about removing some stuff though. My battery's also working for now, but I figure I'll head to LifePo once this one bites the dust, they don't seem too much more expensive than a standard unit, depending on what you get.

Tradd's photos came in right after my last post, of course. My two favorites:

https://cimg7.ibsrv.net/gimg/www.mia...7c4ab35cfc.jpg

https://cimg2.ibsrv.net/gimg/www.mia...1c36446533.jpg


Anyways, on to more recent developments.

As promised, I got out to the junkyard and raided a few BMWs, and a surprise guest.

https://cimg8.ibsrv.net/gimg/www.mia...284bfdc57f.jpg
I checked the yard stock list two days before and there was no Miata shown. I grabbed a few bits, but when you've got the latest and bestest spec Miata, there aren't that many parts you want to swap.

https://cimg9.ibsrv.net/gimg/www.mia...8acce5766e.jpg
This guy got an LS for $150 (two man carry, 2x $75)

https://cimg3.ibsrv.net/gimg/www.mia...bec2bd25c4.jpg
Not a bad haul for $75. I would have liked to grab more stuff, but my friend was whining about missing his wife or something. Lame.

I got the ABS/DSC pump, Yaw sensor, wheel speed sensors, and wiring off of two E9x cars. One system is an 820.3, one an 870.3. I'm still working to gather as much information as I can, but as I understand it the 870.3 is known to be reprogrammable. Unfortunately, the 870.3 car had a sunroof left open and the yaw sensor was underwater when we found it. Inside the connector was dry, so hopefully the sensor is a well sealed solid state item and will dry out with no issues. We tried to pull some wheel speed sensors off of a Chrysler 300, but found ourselves lacking big enough tools. I'm worried that they'll disintegrate on removal anyways, but I may give it a shot later instead of just buying new. Once I got home, I also went ahead and grabbed The Wingman approved cable. Next steps are to do a whole bunch of research so I can start bench testing components.

Of course, being a hoarder, I grabbed a lot of the junk I found in the Miata and raided a bunch of other cars for good fuses and relays.

https://cimg2.ibsrv.net/gimg/www.mia...5db632de9d.jpg

I bought a spare set of Stoptech Sport rear pads off Amazon and they came in plain white box with no hardware included and the pads in different plastic wrap than usual. They're probably fine but it gave me the wrong vibe. So I returned those and bought another set, this time off of Tire Rack. Despite this massive shipping box, they still couldn't fit the hardware in there. At least the box is correct and I have more faith they're not rejects. Stoptech really seems to have suffered since the bankruptcy, so I may need to find a new favorite brake pad soon.


I also signed up for a VIR track day with the Porsche Club next weekend - $150 for almost 3 hours of track time is well worth having a constant point by going on. Of course, to meet their standards I'm going to have to have an approved shop give my car a tech inspection. I guess they are keen on living up to their cars heritage.

I have run Alfa and Porsche track days here. The Porsche people got so peed off being passed that they stopped taking entries from MX5s, the Alfa people also suffer getting hosed off, but they take it in good part, and we remain welcome there.

I did some detail work to the car getting it ready for the PCA track day, which as I said involves my car having a date with a qualified mechanic. That'll be tomorrow. Rossini Racing is a local Spec Miata shop and they've agreed to give my car a once over.

I gave the underbody a clean and inspection after our little off track excursion. All is well and the car tracks just the same as before the track day, but I wanted to get the dirt off so it was obvious I'd looked at the car myself. The oil is at just under 4,000 miles, so I am going to send it on another track day. Previous oil analysis didn't show any oil deg after 3 track days, which lines up with my temp readings at the last track day. I'll give the suspension and brakes a torque check and regrease when I change over to the RS4s tonight.

https://cimg9.ibsrv.net/gimg/www.mia...6366298f54.jpg
I fixed the tear in the lip. I epoxied and riveted a piece of plastic on the bottom half, and the top half got fiberglass and epoxy. All tears had a stop hole drilled at the end of the crack.

I may try to find a way to cleanly cut the lip so that the outer portions can be quickly removed for service. It's just too low for trailers and my service ramps, both of which are major convenience items. Removing the self tappers repeatedly any time I need to trailer it isn't going to work.

https://cimg2.ibsrv.net/gimg/www.mia...4b4ea722fe.jpg
Something like 8 years ago, a glut of Suzuki Cappuccino bottles became widely available in the US for like $40. I grabbed one and put it on the shelf in case I ever needed the space in the engine bay.

That time has arrived.

https://cimg3.ibsrv.net/gimg/www.mia...22a2589d0c.jpg
The Mk60E5 unit fits where the washer bottle used to go, between the fuse box and A/C lines, as if it was always meant to go there. It's hard to capture but there's more clearance all around the unit than there appears to be in this picture. Everything looks like it will be pretty serviceable after install. I've tried a few different orientations of the unit, but my first inclination shown above still looks to be best. Designing a bracket to support this will be fun!

My programming and diagnostic cable arrived as well. There's a few more parts to grab before I can give my parts a bench test and start working to install everything.

I'm at the exact step of about to install the pump myself. I saw this today on Facebook. It's in the same spot you are looking at, just a little different orientation.

https://www.thingiverse.com/thing:65...jOMhrD-B_8gg1o

I can't decide if the plastic is strong enough to hold it long term, especially in an accident or something like that. (I also want to use rubber isolator mounts like BMW did...so would need to look at how to do that if I went this direction.) So I'm leaning towards building my own bracket.

I've installed the Chrysler Tone rings and the BMW sensors already. I used the rear BMW sensors for both the front and rear because it will read from the side along with from the top. I went this direction because Wingman was starting to melt his, and this fits the brake ducting I have too. I also used the old tone rings as spacers (after shaving them down.) Getting those rings installed was a PITA. I think I have 8 hours into just getting the rings on. Here's some pictures if it helps.

Front: you can see the two tone rings in this picture and how I oriented the sensor.
https://cimg8.ibsrv.net/gimg/www.mia...5f17b09243.jpg

Front: I cut off the original stub that Mazda machined to hold the sensor and welded on this little piece of 16 gauge. I welded a nut to the "front" side so the sensor was easier to attach.
https://cimg9.ibsrv.net/gimg/www.mia...74d17ce2b9.jpg

Rear...just a little piece of square with a nut welded in it. This is before I painted it.
https://cimg0.ibsrv.net/gimg/www.mia...aba7dbc53d.jpg

Good Luck with your install. Very interested in seeing what you come up with.

Awesome, thank you for sharing your install! Good to know about the rear sensors being less sensitive to orientation. Do you know if there's a reasonably complete list of what sensors and tone rings will work? Are your sensors and tone rings new? And are you documenting your install anywhere?

I saw the same bracket on Facebook, I think it's a bit close to the A/C lines for my use. And like you, I'd prefer to have the rubber isolators in place. I might give it a test print, but my current plan is to either do Cardboard Aided Design, or 3d print a test fit bracket, then convert it to sheet metal cutouts and have some place like Send Cut Send cut it out for me.

As for heat, I'm so ridiculously over-braked at this point that I doubt I'll have the issues Wingman did. But the whole theme of the build is complete overkill, so I might as well lay out my ABS like the car is going to be pushing 400 hp. Eventually I do plan to get more power, but I've been saying that for probably 6 years now.

So on that Facebook page there is (somewhere) an excel spreadsheet with a list of tone rings on it that may fit. There wasn't a lot of hall effect tone rings on the list, most of them were older VR ones. I looked at the list and nothing would fit my car. (I have BroFab e30 front hubs and V8R Getrag rear end half shafts, so nothing OEM Miata size.) I'm fairly certain Wingman couldn't find a tone ring that would just work (he had Miata half shafts at that time). There is an ABS VR Converter (that is sold out right now) that should work if you have the stock tone rings & sensors installed. https://happycactusgarage.com/products/mk60-companion My guess is that people will ask him to make another batch of the converters. I had to install tone rings anyway, and I figured if that converter piece ever broke, I might not be able to get it repaired / easily fixed, thus why I chose to go this route. As far as sensors, I believe there is also a Mercedes sensor that would work with the MK60e5 if memory served, but it was basically the same sensor as the BMW ones in shape and size.

I bought new tone rings because I didn't think I could easily remove used ones without destroying them. Sensor wise, I couldn't find but one at the pull a part. The others had been removed already and I wanted to use all of the rear sensors because they read from the side along with at the very end. I can find the part numbers for you if needs be. I think I bought the rings and sensors from ebay and it was something like $120 for all of them.

I am going to put all of this in my build thread, but I'm pretty behind on keeping it updated right now. I normally write stuff up once I'm done, but maybe another ABS brake thread on the MK60e5 is the way to go instead. Seems like a few of us are all interested in doing this right now and another write up or two wouldn't hurt. I'm currently looking up and about to purchase the rest of the wiring parts that I need and hope to have the pump and yaw sensor installed in the car this weekend. Happy to share those pictures / how I did that if you are interested.

Yeah, I think it's time we start a new tech thread for Mk60E5 setups. It's going to be different enough from the Mk60 installs that we should gather as much data as we can in one place.

Please post any more info you want here in this thread as well! Easier for me to reference that way.

__________________________________________________ _

The VIR track day with PCA was an absolute blast! I was definitely the slowest car on track, so I had to be on the spot with the point bys. I had one 4-off into T10, after the esses, but that was the only big excitement and it was a pretty tame incident. Once I knew I wasn't going to make the corner I just committed to the off.

https://cimg4.ibsrv.net/gimg/www.mia...1717739cd4.jpg

Compared to two weeks ago, I was pushing deeper into the braking zones and the car was better set up. I was a bit higher on rear tire pressure, went up on the damper settings front and rear, and decreased the rear brake bias. While it was 10 degrees warmer than two weeks ago, and there were a bunch of Porsches that had really rubbered in the track all weekend, my times would have put me as the second fastest Miata in the TT5 class last weekend. My fastest lap still has lots of room to improve.

https://cimg7.ibsrv.net/gimg/www.mia...ed61554717.jpg

I was really proud of this until I checked the results again and found that P1 was 2:22, not 2:24 as I remembered.

https://cimg9.ibsrv.net/gimg/www.mia...807952b3be.png

I have a lot of work to do!

Here's my fastest lap. I'm surprised at the pace, given how clumsy it looks.

Nice work!

Thanks Emilio! It means a lot coming from someone with your experience and background!


I've had a bit more time to digest the experience of yesterday, and here are my takeaways so far:

1. Pad knockback. It seems the BBK upgrade isn't all upsides, and for the first time ever I felt the need to give the brakes a tap with my left foot before going into a braking zone. How low the pedal was at each braking zone was proportional to how hard I was cornering and the number of directional changes. It was at its worst after the uphill esses, and almost like normal going into NASCAR. At first I was worried it was the parts I designed not really being up to the task. I did some thinking and came to the conclusion that if there's any flex between the hub and the caliper, the only way the brakes can deal with it is by opening up the distance between the pads - knockback. Contrast this with the stock sliding caliper, in which the caliper doesn't really care where it sits and can float a bit with the pads/rotor.

I've got Brofab E30 front hubs and Afco F88 calipers. It's pretty much as rigid as you can get the stock upright and braking system.

I asked a few other guys that just installed the F88 kits with mixed feedback... and then I found a post from Savington that describes exactly what I was talking about, at the exact same track.

I love it when I can find an experienced hand can confirm my crackpot theories. Keisler drop spindles with stiffer bolt on MR2 hubs, and floating rotors with sprung anti rattle clips are distant daydreams, so I'll just keep giving the brakes a tap for the foreseeable future.

I'm guessing that this wasn't really an issue last track day because the pads were so new, there wasn't hardly any room for knockback and it would just press the rotor and pad together for extra drag in the corners. Now that some pad has worn away, there's room for the pistons to retract.

2. I'd like some kind of aero upgrades if I'm going to keep visiting high speed tracks. The rear end of the car just is not as confidence inspiring as I'd like. At low speeds it pushed a bit, but without any rear aero in my toolbox, I can't address it without compromising on the fast parts of the track. I don't know if I can stomach the 9LR "Street" wang or a Blackbird style spoiler, which are the actual correct answers for my use case.

Carbonmiata has a nice "longtail" spoiler that I'd have no issue with rocking full time, but I've heard wait times can be around 6 months. I've emailed Goodwin to see if this is something they ever plan to stock as the US distributor for CM.

https://cimg2.ibsrv.net/gimg/www.mia...b586cb8aba.jpg

I just found this "Track Car Aero" wing setup sold in the UK. Trunk mounted and easily removable, and reasonable enough to actually run on the street between track days without feeling like that guy.

https://cimg5.ibsrv.net/gimg/www.mia...9b797c1cad.jpg

I'm going to visit a friend in the UK in May, so I think I'll look into the cost of getting this shipped, vs flying back with it. I wish there was an intermediate option, something between this wing and the 9LR wing, but still trunk mounted. The Cobalt SS and RX7 wings are sort of in that vein, but I can't imagine those bulky uprights and unknown wing profile are doing any good from a drag perspective.

Underbody aero is something I'm still wanting to work on as it's a much sneakier solution. I need to finish up those wheel well liners and underbody spats, there's interference with the hand brake cables that I never dealt with. Also, now that the party primaries are over, I'm cleaning up some of the litter on the side of the roads and adding to my coroplast stockpile. Maybe that can become underbody paneling.

3. Too much rear brake bias is a real problem. In my first session I found that the rear occasionally wanted to pass the front or I'd get rear lockup, especially while trail braking. While I was able to dial it down with the prop valve between sessions (remote adjuster is disconnected), this may not be the ideal combo of parts if I want the prop valve to be just barely adjusted off of the full rear setting for best trail braking. That's what Emilio recommends. ButI'd seen multiple different perspectives on what setup gave too much rear bias between Emilio, Keith Tanner, and Bob Bundy, so I decided to go with what was already on the car.

I need more seat time to really get the feel for this, but I have the calipers and brackets on hand to mix and match any 1.6, 1.8, or Sport brake caliper or caliper bracket.

4. There's only so much improvement I can make in a day. Even my fastest lap looks clumsy with clear gains to be had. Sometimes you just need to turn it in for the day and let your mind internalize the lessons you've learned. I'm sure when I come back I'll be able to find even more speed. And this is the real ticket. As much as I enjoy modifying my car, seat time is the number one mod it needs.

Oh, and I lied about the oil change. I did it the day before the track day. Really, I only posted about this because I wanted to showcase one of my favorite silly tools - an oil filter cutter.

https://cimg9.ibsrv.net/gimg/www.mia...7e397d260a.jpg

I bought this thing when I wanted to see if my Jeep 4.0 engine that nuked a distributor gear had pushed any metal through the system.

https://cimg0.ibsrv.net/gimg/www.mia...4169652326.jpg

The Miata's oil filter was nice and clean. 4k miles and two HPDE days on it.

https://cimg6.ibsrv.net/gimg/www.mia...54dea50bb2.jpg

I don't know why I waited until after the track day, but I took the dust shields off for improved cooling. I didn't want to cut them, so the bearing came off. I'll probably do the same in the rear since I'm running pretty tame pads and shouldn't have to worry about over cooling my brakes.

That spindly little spindle is what seems to be causing my long pedal after the esses at VIR.

https://cimg5.ibsrv.net/gimg/www.mia...c225be49ee.jpg

I've been keeping an eye on the boots that go with my Bauer ELBJs, they've been cracked but still sealing for a while now. I'll need to insulate and shield them from the rotor with the dust shield now gone. I'll start with aluminum tape and find a better solution from there.

Looks like a blast. I haven't been on track at VIR but hoping to make it down this year.

And I'm looking to get to Summit Point or Dominion! I need more track stickers for my back window. I keep my eye on MotorsportReg looking for cheap seat time. I also need to find some local guys doing private party track reservations. Towards the end of my time in Michigan that was how I was getting most of my track time in.

My next event on the calendar is the Gridlife South Carolina Festival. I can't think of anything the car truly needs, but I have some projects ideas ready for it.

Question for you about your skunk2 TB.. Have you had to mess with it at all recently sticking, greasing it, etc? I ask because I just went out to the car to check it since it started sticking at the end of my track day and took a closer look at it. The 1/2" nut loosened a bit (the one nut I didn't loctite of course) so I snugged it back down. Operating the rotor by hand now causes it to make this nice squeaking sound. I'm 90% sure it didn't do this before. Who knows if the loosened nut allowed a little bit extra side to side shaft play which caused some wear and is part of the reason it squeaks now. Trying to wobble the rotor it doesn't really have any play to it. Have you fully disassembled the TB to try and grease it? The squeaking tells me something isn't right on mine. I see some people have tried greasing the spring.. Next time it's off I will definitely have to mess with it..

Regarding a wing, I'd say just bite the bullet and do the 9LR big wing. I think I will likely go that route when the time comes as well. Do you drive your car a lot on the street?

Nice drivin' and recap! Super sick to see you would've been 3rd overall in TT5. Do you know anything about the setup the Miata with the 2:22 was running?

No idea, I wish I had gone and looked at his car more closely. I did some digging and I'm guessing he's a been a regular there for a long time and has modified his car quite well to the rulebook to be 4 seconds faster than the rest of the field that's only separated by 3 seconds. And obviously he can drive!

What you see in this thread (and the condensed S2 TB thread I made) is everything I've done with it. Not sure which nut on it is 13mm/1/2" but I'm guessing the throttle shaft? I went a bit past the paint markings from the factory when I torqued it back down, but no loctite on that part. Other than my stalling issue on warm up, it's been fine. And that I won't even entirely blame on the TB, as I have this warmup misfire I can't figure out. Plus some of the feedback I got in that thread indicated that it could also be due to the IACV getting to be past it's prime.

As for how else I drive this car - it's my preferred daily. If it's not torn apart or absolutely pouring rain out, this is what I drive. For a while I was regularly driving 11 hours one way to visit my GF in North Carolina before I left Michigan. That's why I'm not exactly eager to get a big attention grabbing wing that won't come off without leaving a panel gap for everyone to see. Usually the only thing that changes between a Friday commute or date night and a Sunday HPDE is the tires. If there's a long time between events, the race seat will come out.

The caveat to my last post is that dual duty cars aren't daily cars you track, they're track cars you try to drive to work as often as possible.

I had heard a shudder or vibration when I was braking in reverse and decided to take a look at my rear pads. I figured they just needed to be flipped.

On the drivers side of the car, I found the caliper pivot pin on the bracket to be completely loose. That was a sobering moment,. I regularly check the bracket bolt torque but hadn't looked at this since at least my last rear pad change.

https://cimg9.ibsrv.net/gimg/www.mia...1e4e87a1f0.jpg
I'm not sure what the threads are on this. M9x1.25? Neither my M8 or M10 dies would thread on. I cleaned it up with hand files, then cleaned the threads both bolt and bracket with brake clean before smothering them in red loctite and torqueing to 25 ft-lbs.

https://cimg6.ibsrv.net/gimg/www.mia...a93d45d84b.jpg
This definitely caused some uneven wear on the pads.

https://cimg3.ibsrv.net/gimg/www.mia...201cac8bf1.jpg
Woof.

https://cimg0.ibsrv.net/gimg/www.mia...2c8ecc5bbf.jpg
The new Stoptech 309 Sport pads have a different backing plate shape. They must have changed the manufacturing plant, I have heard they are moving operations to Mexico and there may be a dry spell of parts, assuming they continue production. Hopefully these pads remain available.

I'll be stealing this quote lol. Spectacularly put.

Glad you caught that pin before the issue turned into something worse. Maybe the photo is just out of focus, but I'm surprised you were able to bring the threads back on that thing. From the pic, it looks like they were all but completely flattened.

That's good to hear. Ya I torqued my nut down a bit more after drilling the hole you suggested but it still loosened up. Oh well. I'm going to start tinkering with the car again this week so we'll see what's up with the TB.

That makes sense. Ya I'm not a big fan of driving with a giant wing on the street either but I might make an exception for this car when the time comes. My car won't see many street miles though. On my Honda I can easily swap trunk lids with a big wang mounted to it but with the 9LR wing being essentially chassis mounted it doesn't look like there's an easy way to remove the 9LR wing in between track days.

I made it out to Gridlife South Carolina for the second time in a row, and again, I was really only there on Sunday. Unfortunately they sold out of camping spots while I was making the last minute decision. Springtime means there's a lot to do around the house, too much for me to get a hotel to spend a day looking at cars. One year I'll make it out to the whole event!

I drove down there this morning in the Miata, with the RS4s already on the car, and a minimum of tools and spares. To summarize, I got a best lap of 1:56.3 which is right about in line with where I was last year IIRC. I'll take that as a good improvement for running on RS4s instead of RT660s. I got about 2 hours of track time total - the last session was an hour, and I could have gone longer. I had to stop for gas once, and with about 15 minutes left to go I decided I'd had enough fun for the day. I wasn't as consistent, and I could tell the tires were getting tired too.

I cursed myself a few weeks back by posting in @Z_WAAAAAZ build thread.

I had came into the weekend wanting to play it safe, but at some point in the third session I decided the risk was worth keeping my foot in it on corner exit just once or twice. CMP curbs are absolutely absurd and punish anyone who dares go wide, and I was a victim. Eventually I noticed my steering wheel was pointing straight ahead, when it had a slight left tilt beforehand. a look under the car after the session confirmed that the two camber bolts were not at all in the same position. I ran around the paddock looking for anyone with alignment equipment, and eventually found a guy with toe plates he was willing to loan me. I used the toe measurement as a substitute for camber, setting it back to the original setting. This took a few tries, then I cranked down on the camber bolt real hard and hoped for the best.

I'll be ordering the new Supermiata upgraded bolts here soon.

Anyways, here's a few pics from the day.

https://cimg1.ibsrv.net/gimg/www.mia...0e4569a018.jpg
I was first to grid for the Advanced group, and soon regretted it. I'm pretty outgunned in this crowd.

https://cimg9.ibsrv.net/gimg/www.mia...48052024de.jpg
I got some ice cream out of the cutest little Subaru Sambar.

https://cimg4.ibsrv.net/gimg/www.mia...6b39763989.jpg
Neat.

https://cimg2.ibsrv.net/gimg/www.mia...581b02706a.jpg
And this is why I could never actually do drifting as an event. That is a staggering number of destroyed tires, and several destroyed wheels.

https://cimg5.ibsrv.net/gimg/www.mia...42e4b77bcc.jpg
I'd never seen these Rush SR cars before, but they look to be my perfect racecar. Simple, small, low cost commodity parts, and a sportbike soundtrack. Too bad the buy in is $40k!

https://cimg9.ibsrv.net/gimg/www.mia...25864a93b1.jpg
Somebody absolutely wadded up this Sundae Cup Fit.

https://cimg3.ibsrv.net/gimg/www.mia...b5c2b8d709.jpg
The coilover mounts on this car are nightmare fuel. Also, that air filter location!

https://cimg3.ibsrv.net/gimg/www.mia...7caa743297.jpg
That's not what a fuse box should look like.
https://cimg0.ibsrv.net/gimg/www.mia...c935e2e562.jpg
I saw this guy pulling a car onto his trailer with his truck and knew it looked sketchy. Within ten seconds, the chain caught on his tire rack and tore it down.

https://cimg9.ibsrv.net/gimg/www.mia...bbe44481e4.jpg
I finished the day by hanging out with some Miata guys.

Gridlife is such a strange event. There's some insanely cool cars and great engineering. And then there's some real head scratchers.

Hey that dude with the orange miata is the guy who 3D printed like 100+ parts and all the aero for his car, right? I've been following him on instagram for a bit. That thing is super cool!

Looks like a good time, man. Running the same time on RS4s vs RT660s is a solid improvement for sure! Glad it was a good weekend aside from the alignment conundrum. I'm sorry for bringing the bad bolt juju to the track with you :rofl:

Yep, that's him! We talked for a bit to catch up as I'd spoken to him last year. He was having issues throwing belts off of his Rotrex supercharger back then. A few washers to shim the pulley in alignment was all it needed. It was super cool to see the 3d printed air dam, wing, and side skirts. I've been disappointed with how I can't find what I want in the aftermarket for a few items. For the past few weeks, I've also been thinking of upgrading my laptop and buying a 3d printer of my own. Seeing his car was definitely a kick in the pants to get that going and spend some of my bonus this year. I hope I see him again this year, it's always nice to chat with someone who wants to do things their own way.

The alignment bolt juju was my own doing, I didn't knock on wood! Plus, now that I'm doing more alignments myself and being on gripper rubber instead of 300+TW tires, this was inevitable. And honestly this is a great lesson. I've been meaning to expand my alignment gear setup, so a set of toe plates will be a good addition for quick work at the track.

I forgot to mention the biggest lesson learned of the weekend! I've always been pretty aggressive with my heel-toe downshifting. With the heavily front biased stock setup, getting those shifts in ASAP and keeping the engine close to redline was effectively moving the bias rearwards and getting me more overall braking ability. Plus it sounds great. But now that I've got the Afco setup that moved the mechanical bias to the rear, I was running into issues with unstable braking. I've been backing off on the rear brake bias with the proportioning valve, but going forward I'm going to try to do some driver mod and focus on breaking old habits.

Great photos! Sounds like a fun weekend. Gridlife seems like an awesome event.

Do you think the break bias is a crutch for bad form? I would think you'd want to run slightly biased towards the front.
I could've misinterpreted what you said.

I remember reading more than once that if you have the option to adjust brake bias manually, it's best not to rely on downshifting for additional rear bias. Actually one of the books I'm reading right now drove the point home to downshift deep into the braking zone so that, additionally, you can focus on threshold braking before you have to heel-toe. I'll have to find the passage and post it up here.

I downshift too early somewhat frequently, although not consistently. Really depends on how in control I am before entering the corner, and has never had anything to do with trying to set my brake bias. Lots of things to do while driving a relatively-fast, manual transmission car with no driver aids :rofl:

Props for working on breaking old habits! I tell myself that some of the reason my mountain bike career never took off was because I was too stubborn to take a step backwards and change up my technique/eliminate old habits lol.

Well, I don't think that's the most flattering way to put it, but on the face of it I can't say you're wrong.

When I was working on my BBK, I did some quick and dirty math based solely on rotor OD and caliper piston diameter to get context for all the opinions out there on proper brake bias. Might as well share it now.

https://cimg2.ibsrv.net/gimg/www.mia...1ea44e92b5.png

Mind you, I stand behind none of these figures, I am not a brake engineer. This is far from an exact figure at any point while you're braking - realistically you need to look at the system pressure you've created with the brake pedal, factor in the proportioning valve knee point and curve, and use the centroid of the pad instead of the outside edge of the rotor, pad temperature vs friction coefficient curve, etc.

But it does give context for what's going on. Since I started with a Sport package braking system, I have the most rearward biased brakes from the factory. Based on my experience so far, that is still too far forward biased for straight line braking on 200tw tires without any engine braking. Manufacturers set it further forward than ideal for the racetrack this because it's safer for an inexperienced driver in a panic situation.

My ideas on how that has affected me so far is that the excessive factory front bias let me develop my driving habits in a way that was very aggressive on downshifting. When I went to the Afco calipers, I actually reduced the effective front braking force for a given brake pedal pressure and moved the brake bias rearwards as a result. Now that the rear axle is much closer to the limits of traction just from the braking system alone, engine braking has a much larger effect on the car balance and I can exceed the limits of the rear tires when the two are combined. So, what helped me with stock brakes is now a bad habit with the BBK.

I typed all this out before I remembered a professional already spelled it out far better than I can.

Supermiata Brake FAQ | 949 Racing

Please share if you come across it! I love it when I discover on my own what professionals knew long ago. I mostly went down this line of thought after realizing I had no instability issues when I knew I overshot the braking point, and only focused on the brake pedal. Fixing this habit and experimenting with going back up on the brake bias will be a project for another day though.

That brings up a good point - I set up my car for a remote bias adjuster cable, but I've yet to get it actually working properly. Once I remount the prop valve at a different angle, and shorten the cable to remove some of the twists and turns it was taking, it should be more effective.

I also need to get a passenger race seat setup and start asking for instructor ride alongs. It's been years since someone more experienced than me was in the passenger seat.

https://cimg3.ibsrv.net/gimg/www.mia...742c93e5d.jpeg

https://cimg6.ibsrv.net/gimg/www.mia...2b737f347.jpeg

Found ‘em! Maybe I need to reread the passage. I remember the point being driven home to downshift late into the braking zone, but forgot about the bit regarding getting your downshift done before entering the corner.

Your brake bias findings and resulting downshift technique make absolute sense, though. I seem to remember NA8’s have the most frontward bias, and after tracking my car for a while, I began to do the same thing with early downshifts, although I didn’t know why I was doing it at the time lol.

This book generally assumes the car being driven is a race car with an adjustable/dialed in brake bias, so a stock Miata may not be covered by said passage.

Well TIL. I always assumed that adjusting brake bias via a valve had a major effect on the overall system. I guess I never thought about it too critically, but it makes sense that if you have massive brakes at one end and tiny ones on the other that there would be an imbalance.

Good reading material from both of you. Cats for everyone.

Since I've decided this car is too reliable to go and make a mess of the engine, I finally decided to get a cold air intake. I was planning out the design and what parts to use when my buddy said I deserved a little treat and to just get a bolt on part.

So, I ordered the Cobalt CAI because it's the most complete one out there, and on sale.

https://cimg7.ibsrv.net/gimg/www.mia...66e5a27c1d.jpg

I've only driven with it twice, but so far I love it. I don't care if it makes more power, I just want that intake HONK. It sounds great!

https://cimg5.ibsrv.net/gimg/www.mia...f247c3596f.jpg

I also scored this hood for free off Marketplace. It was in an accident and apparently has a bend in it. All I could find was a small wave in one spot, and that the skin and frame have separated a little bit. I had to take the gas tank tin as well.

None of that really matters though, I'll cut this one up and add vents for a summer track day hood. I've never wrapped anything before, I might give it a shot on this.

Score on the hood! Any idea what vents you're going to go with? Any thought to a DIY venting solution?

I'm not sure yet. Most likely the R Theory units or something similar, but I would really prefer something a bit more aesthetically minded. I'd be willing to go to hood pins as well.

I need to get a better computer so I can start to learn to model off of 3d scans. Padlock is putting out some good stuff, and I have other things I'd like to create as well.

I downloaded Polycam recently and was impressed with the scans I was able to get just from my phone. I tried it out for fun, but when I was at the store looking for some materials I actually pulled it out and looked around in my engine bay scan to reference. I think there are limitations on the free version, but its worth a shot if you're getting into that space.