Watterson02

I bought the car in 2019 for $3500 with 99k miles on it. It had a torn soft top, non functioning speakers, and dry rotted tires. After fixing the speakers and putting a new top on, I threw on some 16x9 Advanti Storm S1s with a 215/40/16 Federal 595 tire. Took the rollbar and cheap Tein coilovers off of the old miata, and sold it. Some time early here, I was backed into at school. The passenger door was replaced and paint matched after the other driver admitted fault. I also found another trunk lid with the spoiler for added #racecar. Threw some BFG Rival S 1.5s on the stock wheels and autocrossed it with the East Tennessee Region of the SCCA. Got to meet TNTUBA there and see his awesome car.



Soon there after I bought a MS2 PNP, learned the basics, did some stupid stuff, but surprisingly didn’t blow up the motor. Initially I had an Innovate MTX-L which went through at least one O2 sensor a month, sometimes 2-3. I’m pretty sure autozone hated me for taking advantage of their warranty haha. Anyways that junk was replaced with an AEM Eugo without changing the wiring at all, and since then I’ve not gone through a single sensor.

At this point I also installed a Cobalt Radiator with their coolant reroute and a 160° thermostat. This thermostat would later be replaced by a 180° because in the winter the coolant temps wouldn’t go over 140°. Due to my own ignorance I installed their radiator, which is incompatible with AC, with the AC still installed. This resulted in a bolt to the AC condenser rubbing the radiator and eventually rupturing it at an autocross. My being the cheap idiot I am JB welded the hole and it’s held since I reinstalled it after the turbo went on

Anyways, Covid ended up coming around, I got laid off, and got some of that sweet stimmy money from Joe Brandon and blew it all on turbo parts. With used Flowforce 640cc injectors, a machined eBay cast manifold, and an open box Garrett 2560R all that I purchased from this forum’s members I got to work. I got all of the equipment needed for the exhaust from ATP Turbo and Ace Race, and the intercooler and piping from Silicone Intakes. Shout out to my awesome grandfather for teaching me so much, helping me (not just the welding), and letting me steal his garage space.




Soon thereafter, I blew up the 5 speed, swapped in a 6 speed with a “lightly used” FM clutch (I say lightly used because it looked like it had seen more miles than the seller said). Next I wanted to see how it would do in the quarter mile at Bristol Motor Speedway. I don’t remember the exact numbers, but I think it was trapping 99 or 104 MPH, I don’t remember. And this is with what I suspect to be a 4.3 diff and 6 speed… lots of shifting to be done. One of those runs however, I miss-shifted. I was trying to grab 5th from 4th, but got 3rd gear instead. Datalog showed 8350 RPMS… not good. Once again, me being the idiot I am, I didn’t think to check if I bent a rod, which I suspect that I did because a month later… this happened the day before an autocross:




So I swap in another motor that I pulled from a friends part car for $500, thinking that I’m fine now I started ripping on it again. I noticed the harmonic balancer had a slight wobble, but I thought I’d get around to fixing it later. I just wanted to drive the car again. Bought some 15x9.5 Konig Freeforms wrapped with the 245 Maxxis VR-1 for AutoX, sold the Advantis, and daily drove on the stockers. Here’s a pic of the Freeforms:



Not long after, I hit a deer on my way to work at around 30 mph. I didn’t even see him, but he kindly **** on my car, dented the hood, and caved in the fender when I hit him. I popped the fender back out and was on my way.

Not long after that, I was on my way to Wally World, gave her a good 7000 rpm pull and heard that dreadful knocking sound. Spun a bearing. My main hypothesis is that it spun a main bearing due to the aforementioned wobbly damper, as it had plenty of oil at the time. So I limped it home and parked it there, and then eventually towed it to my dads house where it sits today. I went by there recently and noticed that the clear coat is peeling pretty bad now. Mainly on the hood and near the gas cap. I should’ve thought to cover it when I parked it out there. Oh well guess I’m just gonna have to look into wrapping it (I like the 3M dragon fire red) or painting it.


Now, for the third motor I was able to source a running NA8 motor for $500. I’ve disassembled it, measured the bearing surfaces, and confirmed that it is all within OEM spec. I plan on refreshing and reusing the head from the motor with a spun bearing. Today I order the new internals. The parts list is as follows:

• 83.5mm 8.5:1 Wiseco Pistons
• Manley Connecting Rods
• Boundary 2 Shim Oil Pump
• Fluidamper
• Supertech Heavy Doubles Valve Springs (gonna try to reuse the original valves and cams, but wanted the ability to run slightly more aggressive cams in case I wanted to upgrade the turbo later and shoot for bigger HP numbers by revving to 7800 or so without making transmission breaking amounts of torque)
• OEM Headgasket
• ARP Fasteners
• Gates WP and Timing Belt
• All OEM Gaskets

I’m super excited. It’s been too long without the Miata. I plan on taking it to Center Street Machine in Kingsport TN as he has worked on my buddies miata engine (see his Instagram for an 85.5mm Supertech itb build: ITB.Miata). I will have him clean the block, refresh the head, spec the bearings I need to order, and then have him assemble it for me. Figured I could do it myself but the peace of mind knowing it’s done well is worth the extra money IMO.

Watterson02

Two weekends ago I pulled the head in my dads gravel driveway in 90° heat. Not too bad, got it done in about 2 1/2 hours by myself. The biggest struggle was the exhaust manifold/turbo. I couldn’t get the middle exhaust manifold bolt because it’s too cramped and my wrenches wouldn’t fit. Ended up having the head loose, scooting it forward, and removing the turbo with the downpipe still attached. No shaft play so I can’t quite justify a bigger turbo yet. I was almost expecting some from not running a BOV but nope just the normal amount.


Now just to get it all to the machine shop. I wanted to go just about all out as I can with this motor so that if it lasts, I’d never have to take it back apart. That to me means bigger valves, maybe replacing the valve guides, smoothing the short side radius of the ports, SUBs, and springs.

After looking into it I decided to opt out of larger valves for the time being (assuming the stock ones don’t need to be replaced). I’m also skipping the SUBs as I don’t plan on going with aftermarket cams currently, maybe an Exhintake with adjustable cam gears before the machinist gets it to set the shims up. Maybe rev to about 7600 since my current shim over bucket lifters won’t be too happy over that.

anyways here’s a list of my planned machining. Will probably do the SSR porting myself, leaving the rest to the machinist

Head:

• Hot tank / clean
• refresh valves/seals / replace with +1 valves I f needed (are supertech valves still considered a common failure point?)
• deshroud valves
• smooth short side radius
• Inspect/replace valve guides
• replace valve stem seals (OEM)
• install supertech valve springs and retainers
• resurface

Block:

• hot tank / clean
• bore / hone to 83.5mm using wisecos recommended piston to wall tolerance
• polish crank bearing surfaces (still need to order bearings, just wanted to get confirmation from the machinist on bearing size)
• balance roatating assembly

Overall, I’m really excited to be getting to this point. After lots of thought and research I feel like I’ve got just about all of the low hanging fruit (like smoothing the short side radius) and have made good decisions on skipping what I don’t need like the SUBs. Now I’m going to look around locally for a BP4W exhaust cam and adjustable cam gears before getting it to a machinist (pm if you got one and wanna let it go, I was think $150 would be a good price). Only complaint is how long it’s taking to get stuff rolling with work getting in the way, but it’s only going to go worse when I return to college on the 22nd this month.

Watterson02

A small but sad update: The machine shop has had my motor for about a month. I called to see if they’d made any progress yet, and they hadn’t even touched it yet. Oh well.

I found a BP4W Exhaust cam that was already trimmed on FB marketplace. Bought it for $150 shipped.

I picked up some Manley +1mm intake and exhaust valves. Dropped them off for the machinist.

I’ve also picked up a flat top manifold and Skunk2 TB off of a member on here instead of going with Skunk2 intake manifold and throttle body like I had originally planned.

Moving forward, I still need to get a clutch (my clutch decision/recommendation thread), a new fuel filter, my fuel injectors cleaned, and some other small things. Maybe I’ll get a bigger fuel pump while I wait too.

Panici

Following to see progress.
I eventually want to build up my spare B6-ZE. Hopefully before I pop the original.

Watterson02

Oh boy has a lot happened since the last update. I’m definitely going to miss a few things that I’ve done since it’s been so long since the last update. But here we go…

I eventually got the car to my grandparents which is much closer to me (20min from my apartment vs 60-75 min at my dad’s). I pulled the motor, disassembled it, and found that I didn’t spin a bearing. I had actually bent 2/4 rods and the knocking noise was most likely from them making contact with the piston/sliding on the wrist pin. Or at least that’s my hypothesis. There’s no marks on the bore or anything like of the sort that could indicate otherwise. Turns out I didn’t need another core motor, but hey on the bright side I know have a perfectly good core BP4W block (minus the conrods).



Now with the block out, and the engine at the machine shop I decided that I wanted to paint the engine bay in my spare time. I gutted the bay, sanded it down, and painted it. It looked great. Emphasis on looked.





And just to make it a little shinier I went to apply a clear coat. This is where the **** up occurs. Me being in a rush, and not having much experience with painting stuff, I just got the first can of clear coat I saw from a parts store. Turns out it was “Peelcoat”, aka plastidip clear coat. The solvent caused it to soften up the paint, causing orange peeling and a cracking look in a few spots. I considered sanding it down to start over, but that’s too much work and I didn’t have high expectations in the first place. If it starts to peel, I’ll sand that region down and touch it up. Or just ignore it… we will see what happens when the time comes.




And to finish off the engine bay, I installed the Honed Development Brake booster delete kit, along with a wilwood prop valve. Haven’t reinstalled the brake booster yet but everything looks nice. I somehow forgot to take pictures of this so you’ll just have to take my word.

Watterson02

In the middle of doing all of this, a buddy of mine who lives in Knoxville offered me a cheap 2/3s of a black carpet (missing the piece that goes under the soft top). This wasn’t an issue to me since I was already missing the tan one from either the rollbar install or soft top replacement.

So I got to work removing the dash, which is not fun at all lol. Got everything removed (including the unused AC evaporator), cleaned the new carpet, used some sound deadening/thermal insulation that my grandfather had laying around on the driver side to help with the downpipe heat.

From here I installed the black carpet, and started putting the dash back in. I had a snag with the steering colum, but eventually worked it out. Somehow the lower half of the column slid back into the top half and became stuck. Like this there was about an inch between the lower bracket and the firewall. I could not get it to bolt up to save my life. But with a few whacks of the hammer it was back to its correct length and bolted up fine. I still need to connect all of the wiring harness, but everything big is back in place.

Somehow this is the only picture I have on my phone. There’s more pictures on my Instagram’s highlights if you’re wanting to take a look (@watterson02). I usually update Instagram as I go along, so it’s probably more comprehensive than this post, but not as in depth.

Watterson02

And onto last night. I started assembling the new engine. I trimmed up and installed the supermiata oil pan baffle. I couldn’t install the oil pan yet as I forgot the oil pickup gasket, and I was not about to risk it with a homemade paper one. So I moved onto the top of the motor.

I started putting the headstuds in but soon realized some of the threads inside of the block were either rusty or had gunk in them. So I had to stop there for the night and order a M11x1.5 tap from NAPA. Picked up the next day and went to work. Turns out there was a lot of **** on those threads. It cleaned up well though.

I installed the headstuds after cleaning the deck of the block and the head’s surface, then sprayed the headgasket with a copper spray, and put it all together. The headstuds at the back of the motor only had about 1/8th an inch sticking out, so I backed them out as little as I could to get the nut fully threaded on. From there I torqued them down as ARP suggests. Starting at the middle in 20lb-ft increments up to 65lb-ft. Starting to look like I actually know what I’m doing now.







And that’s where the car is at as of last night. I plan on going back out today to do more. I’m trying to have it ready and broke in before a Test n Tune + autocross on March 4/5. We will see what happens.

im currently waiting on a few packages too. I just placed an order for FF960 injectors from Flowforce, a Walbro 255lph from Fab9, and a phenolic intake manifold gasket from skunk2. So far I’ve not had any update from Skunk2 on shipping or processing my order for that matter, but I feel like it won’t hold me up from making more progress.

I’ve also added a few other parts to the build because I clearly hadn’t spent enough money already. For example the Flowforce R8 ignition coils, and a 3.63 ring and pinion (this will hopefully go in after the first autocross). I’m sure there’s other stuff I’m forgetting but it’s such a big parts list, it’s very easy to make this mistake.

Watterson02

So I realized I made an oopsie yesterday. Can anyone tell me what’s wrong with this picture? (I already know what’s wrong but see if you can find it)

?

Stealth97

iTrader: (5)

How the **** do you put a head on backwards

curly

iTrader: (25)

If you’re any modern engine, that’s actually correct.

Watterson02

answer: because I’m a very special individual. In reality, I blame (other than not paying attention) the orientation of the motor and the stand. I’m my mind I had the front to the left, but in reality it was to the right.

If it makes you feel better (it makes me feel better) I at least got the head gaskets orientation correct.

Watterson02

So I’ve had it running for about a month now and things are going pretty well. After having some issues with the oil system priming we finally built oil pressure and got it started on the second turn of the key. First attempt we didn’t have any spark/maybe not even fuel as I forgot to reattached the from crank angle sensor. After reinstalling that we got it up and running.

I took it down to autozone for the maiden voyage to get something a new timing light, and then around the neighborhood after setting timing. Got a few miles on it then came back home to do an oil change. Changed the oil and drove that for about 1000 miles before changing it again and going over to Rotella T6 from conventional Valvoline VR1. It’ll be as little as 10kpa MAP when under heavy decal so I believe the piston rings sealed well. After the first 500 miles or so I started adding in more boost. Up to 14psi or so. Once on synthetic, I turned it up all the way. Ended up seeing as high as 21psi peak falling down to a little over 17psi by 7000rpms. Virtual dyno says 270whp/280wtq iirc. I’ll get the image from my laptop when I get a chance.

One of my favorite changes made inside the engine bay was the Honed Developementa brake booster delete. It’s super straightforward on installation and makes a huge difference. It’s not too bad in terms of pedal pressure either. It’s a good bit up from factory, but I’ve got no issue driving it with my sprained ankle. It really helps in terms of modulation. With Hawk HPS brake pads it’s easy to stop. Highly recommended.

The Flowforce R8 ignition coils are very nice too. I’m using the out of the box plug gap on the NGK BKR7Es and running as high as 16:1 in cruise and 11.7 at 21-17psi with no issue. They’re great and work well with the DIYAutoTune MS2PNP.

Also, during this time I won the set of Tecna Coilovers from Supermiata on Instagram. Took a couple weeks for me to finally get them installed, but I’ve got them on now. They ride very well compared to the old *** Tein coilovers I had on before. This is with the sport springs and the damping 8 clicks from full stiff. For those who want the best ride possible, I’ve got no doubt the street springs with less damping would be great for you. Overall I would strongly recommend these to anyone whose car is a street car/dual duty. For track people/people who want to be low with a good ride quality, the Xidas are probably what you want.

TLDR: I’m very pleased with these coilovers and would strongly recommend them for a street/dual duty application.

Watterson02

Also, for whatever reason, the base map I started with way back in 2020 had it set up for batch injection. It was also set to 2 squirts alternating (I don’t fully understand this part and I’m not going to act like I do). I saw in other basemap, including the one from DIYAutoTune, it was set to sequential with 2 squirts alternating, but this caused my car to miss. Sounded like it was running on 2 cylinders. After setting the squirts per cycle to 1 and simultaneous it did run on sequential.

I ended up reducing the VE under cruise by as much as 20-30% and the VE at full load by ~10%. It feels much more responsive too, but I’m not 100% sure why it had to be set to 1 squirt simultaneous when others show 2 squirts alternating. Maybe someone who is more experienced could chime in here? I’d love to know the difference.

I’ve read a lot of conflicting information including something to the extent of “after going to sequential the squirts per cycle are overruled by the sequential setting” but that doesn’t explain why it had to be set to 1 squirt per cycle simultaneous. I also thought that by setting it to simultaneous that the injectors would still be firing in pairs (you know like simultaneously) making it times batch injection, but the changes to VE and accel enrichment indicate otherwise. This is with a DIYAutoTune MS2PnP btw

Watterson02

Virtual Dyno (270whp-288wtq): AFRs still need some working on but you get the point.



Sequential Fueling: I guess its more like 5-15% difference, but still an improvement nonetheless.

Batch Injection:

Spark Table: Any thoughts on adding any more ignition timing? I'd like to be a little higher in HP but haven't paid any attention to knock yet due to it being conservative. I plan on using the headphone jack on the MS2PnP, but I've not even tried it yet to see if it works/needs volume adjustment.

Watterson02

Well not a lot has changed with the car since last posting. I've just been refining the tune, adding in ignition timing under boost while listening for knock, and recently I've been starting the process of painting a new front driver's side fender since my current one was messed up by a deer a few years ago. Anyways, recently I've been wanting a larger turbo since my engine can now handle the extra power. Additionally, it turns out I fudged the numbers in Virtual Dyno, so a more realistic WHP number is ~260whp which leaves me wanting more. I don't even spin my 195/50/15 all seasons in second gear, which is not very good for my street cred. lmao

The main points:

• Budget is one of the biggest constraints so I'd like to avoid buying a new manifold and downpipe. If money wasn't a constraint, I'd just go buy a kraken low mount and genuine Garrett G25-550. However, even with a pulsar clone and the top mount manifold/downpipe combo I'd still be looking at $2500 or $3000 for the full exhaust to be included.
• I already have the (in)famous tacotaco ebay manifold, which leaves a lot to desire but for $100 you can't expect it to be the best performer.
• I can fabricate my own downpipe, but I was hoping to not have to. If I could reuse my 2.5" exhaust with my RS3 muffler (which proved to not be restricting my power at my current power level through Virtual Dyno testing), it would be prefered. However, going to 3" would help my shitty manifold spool the bigger turbo quicker and it would be better for my 350whp+ goals.
• I'm torn between the Pulsar Gen2 GTX2867R and their G25-550 clone. I plan on going with a Pulsar turbo as they seem to at least have some quality control and partially balanced rotating assemblies compared to bottom of the barrel eBay clones. I'd greatly prefer to go with the G25-550 since it is newer, plus I'd be one of the first to run this turbo on a BP engine. I'd hate to get the 2867R and find out that the G25-550 performs better. Even if it turns out the spool on the 2867R is faster than the G25-550 due to the slightly smaller A/R, I could justify in my mind it by the G25-550 being more efficient. Additionally, if the GTX turbo does indeed spool up faster, I doubt it'd be a huge difference. The reduced backpressure and increased efficiency of the g25-550 is likely going to help reduce knock and in turn it should get me closer to the magic 400whp number.
  • For the GTX turbo, it'll be a perfect plug and play replacement for the GT2560r, however I'd be stuck with my 2.5" exhaust which is likely to be restrictive at my power goals. The Pulsar 2867R is available with an exhaust housing A/R of .64, which is good for spool.
  • For the G25 turbo, I'd be looking at fabricating a new downpipe and then having a generic muffler shop weld up a full 3" exhaust which I'm estimating to end up being $500 give or take. This turbo is only available with the .72 A/R housing, which isn't the best for spool either... but the biggest issue here though is the internally wastegated T25 housing. After doing some quick napkin math and taking a few measurements, I'm calculating that from the outlet of the G25-550 with a T25 inlet and 3" V-band outlet I'd have 120mm to fit in my V-band clamp and a 3" 90 degree bend. The tightest 3" bend you can buy has a 3" CLR which would put me at 114mm and that is without including the V-band flange. That is just way too close to call and I'd rather not beat my firewall in anymore than I already have. So I get on Fusion360 and replicate a 3" bend with a 3" CLR, and I cut out a rectangle that is 1.131" tall at a 45 degree angle. To save you from doing any trigonometry (and brain-fuckery), that results in the 90deg "bend" with a CLR of 2.2". This would bring me up to 94mm + the V-band. I couldn't find the depth of the V-band flange, but this should be enough room to fit it, and if not we can trim up the V-band to make it more shallow, if that makes sense. I've also attached a drawing of the 3" "bend" that I made in Fusion for clarification.
    
    

Now that my napkin math indicates that I can indeed make the G25-550 work, I believe that is the route I am going to pursue despite being $1500+ compared to the GTX route at ~$700. Plus the 3" exhaust should help offset any difference in spool up between the GTX and G25 turbo (if there is any). I know this 90deg "bend" isn't going to flow as well as a true 3" 90deg bend with a 3" CLR, however I do believe it'll be better than sticking with a 2.5" exhaust. When constructing my new 3" exhaust I believe I might go for a smaller straight through muffler or just a resonator only since I'd like the car to be a little louder than it is currently. Anything that I'm missing? If not I think I'll pull the trigger on it in the next month or so.

Newaza

I've been rocking the t3 flange version of that ebay manifold for years.

rdb138

iTrader: (1)

I'm the non-turbo guy on a turbo site, so take what I'm gonna say with a huge grain of salt. Unless you have the stickiest 195 all seasons in the world, a 260whp Miata should have no problem spinning 195 all seasons in 2nd gear. That statement makes me think something is off. Like timing belt has slipped a couple teeth and you don't have much power off.

curly

iTrader: (25)

Or his turbo spools really slowly. Or he has a high ride height with fairly soft springs. But otherwise, I agree. I’d be more interested in the torque map, my guess is it’s pretty soft in the mid range, and the 260 only comes above ~5500-6000rpm.

Watterson02

And I just got this email from BOFI racing... Makes me consider just dropping this turbo in and calling it a day, but then I'd be worried about the spool with the 2.5" exhaust. Newaza, how would you describe the spool on your eBay manifold? I'm under the inpression that my setup sucks nuts for spool, and quite frankly power too.



It definitely isn't the quickest to spool, and I've got the supermiata sport tecna coilovers at decently low ride height. Without launch control or anything like that, I only see 180kpa in first gear and that's right before I shift (keep in mind this is with a 4.3 diff and 6-speed). Additionally, my wastegate actuator setup is pretty janky, makes me wonder if I need to try and increase preload. As of right now peak wtq is around 5000rpms and peak HP is right around or under 6000rpms. This is with 100% duty cycle on the boost controller at 100% throttle across the whole RPM range. Only time it'll "spin" second is when going up a steep hill at full throttle from low RPMs, and even then it's only just barely spinning. The all seasons in question are the TOYO Extensa HP II in 195/50/15 around 34 psi.

There is a bunch of things I could think of that is hurting spool tbh. One thing I planned on addressing with the new turbo is porting the inlet flange to match the eBay manifold. Turns out the casting is the same regardless if it's a T3 or T2 manifold, so the manifold's outlet flange is grossly mismatched to the turbo's inlet flange.

Watterson02

I did a virtual dyno no less than 2 weeks ago and it was reporting 260whp and 260wtq or there about. I am wondering if when I did my exhintake swap if I somehow drilled the cam gear slightly wrong. I was already wanting to get adjustable cam gears to mess with it, but I need one that would work with the BP4W cam sensor. There was one for sale a month ago or so on here, but I didn't end up getting it...

I think my front main seal has a small leak, maybe whenever I finally get around to addressing that I'll throw a new cam gear on at the same time. Anyone know of a brand that works with the BP4W? My google skill haven't been able to find anything...

Edit: I just remembered that I have a NA 1.8L head in my garage. my understanding is that I can use that sensor instead of the one on the front of the engine. Now I just need to figure out how to wire it up. hmmm