Arca_ex

iTrader: (2)

Nice job out there man, congrats on bringing home some of that premium champagne haha. Car looks great in person as well.

You're pretty much right about how the classing system works. If you've got more questions feel free to message me. There are known Miata recipes for most classes from TT4 and slower, and TT is definitely a logical next step or progression from HPDE if you like doing the UMS Time Attack.

Making 160whp on e85 is doable but maybe not as easy as you think, so expectations of a 155 to 165whp range on a completely built engine I would say is realistic. It's exceedingly hard now to build a competitive N/A Miata with a BP in it for TT5, between the power bumps for tire sizing, mechanical throttle body, and tire compound it's rough. And a peak power of 160 is going to calc out for average maybe around 150 to 155 range. On Hoosiers you'd be at the edge of power to weight but having to take the hits for aero to get there. And basically if you went to RR's well, you were already maxed out on Hoosiers there's pretty much nothing you can do.

2409lbs
172whp max average
245mm RR on 9.5" wheels (I think they fit the template?)

-0.7 A-arm
+0.2 mech TB
-0.2 non-OEM brakes
-0.4 comp weight
+1.6 tire mod
-0.5 splitter


But again with a built VVT you could throw on 225mm Hoosiers on those 9.5" wheels and you'd be at the limit of a 155whp max average at 2418lbs min weight.

If you aren't already using this submission form for NASA, it makes doing these calculations extremely easy.
https://form.jotform.com/drivenasa/s...ification-form

flier129

iTrader: (7)

Oh neat another guy that's going to K24Z3 swap and just doesn't know it yet . IMO R7s is the route to go while working with a BP in TT5. Maximize the min-speeds as much as you can!

Also, I know they're ugly as damnit, but an air-dam really helps the entire aero on a NA/NB. If you don't want to make your own: https://9livesracing.com/collections...or-mazda-miata
You can use my discount code: marcussaiditwascool

electroCrunch

@Arca_ex Thanks for the compliment. And thanks for running through all of that. I'm not at a point where I'm ready to jump in, but I do really enjoy the TA format and competition as it motivates me to keep pushing. It's good to know where I'm at now, and where I'd be placed for if/when I want to make that jump.

With running the Hoosiers... I can run those, take the hit for 1.4 tire choice mod factor, and still be in TT5? That doesn't bump me to TT4, it just lessens my allowable max avg whp? I can PM you if that's easier than working it out on here.


@flier129 Lol, for reals . The Kswap idea is always in the back of my head to be honest. If I wasn't so deep into the BP at this point and could rewind time, I would be going that route for sure.

I appreciate the discount code immensely! To be frank, in my opinion those air dams are damn ugly. I have such a hard time getting over it. I know I should care a bit more about function over form on this one, but I just don't like the way the Miatas look with them. It's vain, I know. Maybe if I get to a point where that would get me a specific competitive advantage, I'd think on it a bit more.

Arca_ex

iTrader: (2)

No the Hoosier R7's just make you lose your +1.6 tire mod factor. You would select "Not Applicable" on the calculator. Just start messing with that calculator I linked and you can really start to see how stuff interacts.

Also if you want to do an airdam, you can buy enough material on amazon to make like 3 of them for 60 bucks. Don't buy a pre cut one, they're a ripoff and the radiator inlet size is usually way bigger than it needs to be.

Roda

I got everything except the plastic from Home Depot Racing. The plastic came from Speedway, and is ~$20, IIRC. NAs look good with the air dam, IMHO, NBs not so much. It will definitely make a performance difference on track.

electroCrunch

This is great info , but not what I wanted to hear lol.

electroCrunch

It turns out there is a UMS Tuning Time Attack event this weekend, so I registered for the early morning half day event with NASAAZ. It's gonna be a hot one, but am looking forward to one more event before the summer break.

I had to undo a lot of front end work I was doing (ducting, splitter, etc.) and get it back to its original form for the upcoming event. At my last event I dropped a wheel off a curb, only to have it rebound into my front fender, pulling out the inner lip. I rolled both front fenders, not picture worthy, it turned out fine. I also didn't realize I needed cotter pins in my harness clips, so I pulled the seats out and installed pins. Yay, safer. Speaking of safe, I bought a driving fire suit also.

Other than just a brake bleed and fluids top off, not much is needed to be done to get ready. I even sprung for a mobile tool set I've assembled so I no longer have to pack tools before each event.

The biggest upgrade/change that's going into this weekend's event is a new shifter setup. I decided to be a guinea pig and try out the v2 "fixed" G-Racing shifter. I've been aware of it for some time, but also have been aware of occasional NVH issues at certain RPMs. G-Racing claims they've fixed this. I think now they fabricate the shifter ball end to accept OEM-size bushings, and their shifters now ship with a delrin bushing. I'll be sure to report back how this weekend's testing goes.

Comparison of G-Racing shifter with extended carbon shift ****, versus previous Cobalt short shifter plus a hodgepodge of extensions I used to get the shifter close to the wheel:



Fitting the boot is the trickiest part. It's completely DIY and up to the installer, it's one of the bigger drawbacks to this shifter (well, assuming NVH issues are fixed). I learned a few things on the way. The inner hole of the boot actually has a rubber piece that slips out (where the boot actually touches the shifter). I popped this out and did some measuring. What I should have done first that would have made it all much easier, is drill out center of rubber-thingy to 3/4 inch. Instead I cut the rubber collar first, and afterwards realized I should have drilled it out first so it will retain shape during drilling. Regardless, I used a 3/4" step drill bit and ran it the whole way through which was nearly perfect fit for the 18mm G-Racing shaft. After that, you can move onto cutting the collar (I used a hacksaw because the blade was thin and didn't want to remove too much material).

EDIT: Apparently the rubber collar seen below is from my Cobalt Short Shifter kit, and is not an OEM part to be modified unfortunately. I forgot this piece came with the Cobalt shifter kit, my bad folks. If you have a part number for the collar, OR something similar, please post for others.





After you hacksaw it, it should slip around the base of the shifter like below. I did add some grease between the cut, as well as between the shifter and the rubber collar to seal it up as good as possible. You can see below that it should wrap cleanly around the shifter. I decided to flip the collar so the lip was on the bottom, fyi, before the final install.



Last I slipped the boot over the shifter and slid it around the rubber collar, sealing the shifter boot to the rubber collar. For now I just used a zip tie to seal it all up.



I will report back after this weekend.

Fireindc

iTrader: (13)

Sweet updates! Let us know how that shifter works out, I've been eyeballing one, but if it rattles it would drive me crazy since I street drive my car a lot.

thebeerbaron

iTrader: (1)

Apart from loose batteries and uninsulated electrical terminals, this is probably the most common finding when I do trackside tech for NASA. You'd be amazed at how many of these un-pinned harness clips are on the verge of coming off the anchor.

Sorry you had to pull the seats, that sucks. But thank you for being safe.

electroCrunch

It would drive me crazy too, looking forward to getting off the jack stands and testing it out soon. The shifting feel is amazing just running through the gears, I hope it's a keeper.

I'm glad it was pointed out by the last technician. Happy to pull the seats to keep myself safe.

Roda

Don't want to derail the thread, but this caught me off guard... I had never heard this before, and can't find it anywhere in the ruleset, and it's not mentioned in the installation instructions for my harness (Racequip FIA). I'll be installing cotter pins while I'm doing other work this summer, but it should probably be added to the driver restraint section of the rules.

electroCrunch

Not derailing, valid comment. I was caught off guard as well. I've done many track days with the Miata in this state and it's never been mentioned. At the end of the day I want to be safe, it was just unknown. I do know it's on me to comply at the end of the day, but it was news to me. I will add that the tech inspector who pointed it out, is the head of tech, and the most thorough. It seems that the quality of the tech inspections depends and varies greatly on the individual. Some people have barely looked at my car, others get in there with a flashlight and a fine toothed comb.

The other thing the inspector mentioned is I "should have" harness bar collars to prevent the harnesses from sliding. It's a great idea. I couldn't find any more solid info on that so I posted in NASAAZ forums yesterday to get clarification on that. Not required, but a good idea to have. Just another FYI.

thebeerbaron

iTrader: (1)

It's on both the HPDE/TT tech form and the race car annual inspection form, but you're right, I don't see it in the CC&R. Sometimes these things don't get their own explicit rule because writing such a rule would create more confusion or the like (as I understand it).

I'm surprised it wasn't in your harness instructions, but maybe I shouldn't be - even with a safety system, people don't read instructions, so I imagine manufacturers don't put a lot of effort into them, especially on a commodity like a clip.

We get "No one else has had a problem with my car" a lot, we're used to it. The most aggressive purveyors of this line are usually showing up last minute for HPDE 3 or 4 in either a clapped-out race car or a hacked up street car. I always respect (and try to help) the ones like you who actually appreciate the thoroughness of my inspection.

We have a sign somewhere to the effect of "We don't care what your car weighs at home" for the post-race weigh-in. "I don't care who passed this car last time" would be another good one.

In an ideal world you should be checking the alignment every time you put your belts on, but in the real world, collars are more human-proof. (It's all about the path of the harness between the harness bar and your shoulders. The harness bar collars keep the shoulder harnesses straight in line with your shoulders. Without them, the shoulder straps can slide along the harness bar and either pull the harness against your neck or off your shoulders.)

Gee Emm

Sorry to continue the derail, but can I ask 'photo please'. Where is this cotter pin located? Certainly none on my cars ... and this is the first I have heard of it.

Thanks!

electroCrunch

No problem. If I would have know it would have been the topic of discussion from that post, I would have included a pic.



The pin prevents the latch from moving all the way, so the harness clip cannot come undone.

Gee Emm

Thanks.

20 years of competition, including 6 or 8 with a full blown track car, and nobody here has looked at that and said 'how about safetypinning that catch?'.I must ask around, do you mind if I steal your picture?

/thread derail.

electroCrunch

Yes, no problem.

electroCrunch

Happy to report another successful weekend at Wild Horse Pass Motorsports Park, WEST track in CW configuration. On that note, I'm in disbelief it's likely the last event I'll ever run at WHP, and many other NASAAZ competitors as well. I can't believe they're planning on closing the entire facility down next year. Us Phoenicians have been spoiled to have 4 tracks relatively close to us, it's sad times. Arizona culture is dying quickly lately, this 25 year resident is noticing. We're making way for more casinos, water parks (in the damn desert?!?) and discount shopping malls, oh joy. Anyways... guess that means I'm on the hunt for a trailer again if WHP is outta here

This weekend was an early morning single half-day event. Gates opened at 4am and I was on track around a little before 6am. The day was a bit cooler than anticipated so we got our first 2 sessions extended, bonus. I didn't have any issues with myself or the Miata. It was a great day. I don't have any action shots to share since I'm always driving, but here's a couple pics I grabbed...

My humble setup


Me accepting my Winner sticker. I'm not proud of it though, but I am proud of my time. There were only two TA-A competitors registered that day, and the other participant didn't show up to grid for some reason so I was the only competitor in my class. In fact, there weren't as many participants across the board for the event, guessing the heat scared them away. I seem to put down my PB's during time attack, which tells me I do better under pressure lol. My PB for the day, which was also my fastest TA lap, was 1:09.734. This was faster than a few cars which are classed higher than me, so I'm confident I still would have placed well if more TA-A competitors would have showed up. Not bad for 126 horsepowers.



If you want to watch the full competition, it can be viewed here. At least the banter from the TA director live streaming it, is entertaining:


Let's talk about the G-Racing shifter now. After some solid street driving, and two 20 minute track sessions followed by a TA run, I'm a big fan of this shifter. It's great value for what you get. It shifts excellent, it's crisp, true short throw shifts, and given the extended carbon shift **** the height was perfect (carbon also did not transmit much heat). I never missed a single shift, and I felt like it was easier and quicker to shift gears as well.

But what about NVH rattles?! On the drive back home, in my neighborhood, I noticed in 1st or 2nd in mid-high ish RPMs, there was the faintest of vibrations happening in the shifter. I wouldn't call it a rattle, more of a resonant vibration. I could see how some drivers would be bothered by it maybe if you're sensitive about everything being dead silent in the cabin. However, I didn't even notice it until I was almost home, your mileage will definitely vary. Reminder, I'm on AWR 70 durometer motor mounts, and delrin differential mounts, so I'm going to have a lot of NVH coming through regardless. If I had a street Miata, it would be a tough decision between this and the MiataRoadster offerings. However, for any kind of performance oriented Miata, I really like and suggest the G-Racing shifter. It's not he best shifter on the market, but it seems to be one of the best values available for a real short throw shifter.



Last, I bought a 3d printer about a month ago with the goal of printing miata parts, plus other functional things for around the house. I've gotten pretty good and consistent prints with PLA filament. Now I'm taking it up a notch and trying out ABS which has a steeper learning curve. Here's my first mostly-successful print in ABS. It's a go-pro mount where the visor was mounted previously. Found here: https://www.thingiverse.com/thing:4742400 . Looking forward to getting better with this machine.



There are officially no events for me to attend until October, so I'm planning on getting some work done on the Miata during the long summer break. Stay tuned.

tshea113

I've been using one of these for a few years now that a friend printed out of PETG. It's an nice spot to mount the gopro since there isn't a lot of wind noise and you get a good view of the nose of the car, which I like for recording autocross runs.

Which printer did you get? I just built an enclosure for my prusa mini, so I might start fooling around with ABS as well.

electroCrunch

I'm aware of PETG, it seems to be good for usage between PLA and ABS. I'm going straight to ABS so I can get comfortable with the material, due to its higher tolerance to heat, making it good for parts that might go in the engine bay or near other heat sources. I will try PETG eventually at some point.

I got the relatively new Creality Ender 3 S1. It's been really good to me so far. I think building an enclosure for it is going to be the next big mod, so I can master this ABS material a bit better. I do have an upgraded bi-metal all-metal hot end on the way, so I can crank the heat up on the extruder for ABS. Open to any tips you may have!