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Hey everyone, this is NobyI (CJ), and my 1993 Miata. I had originally started a build thread in 2014 (here), that I occasionally update with event photos, but I'm looking to start a build thread here where I can log more of the various projects, problems, and solutions to reference back in the future. Occam's Racer also has a brief write-up on the car here. Will start it off with a few specs and goals that I will try to keep updated along the way:
Current Specs:
~240whp and 2500lbs (with driver)
Primarily targeting NASA TT4, but also SCCA M3/4, SCCA XB rulesets
Future Goals:
Link G5 ECU, Link PDM, Redo Wiring, MK60e5 ABS, Better Power Curve for TT4 Ruleset (Fix Low Rev Limiter)
2014: Purchased a non-running 1993 Classic Red Miata for $600 with the intent of a cheap STS autocross car while in college.
2015: Swapped another 1.6 into the Miata and painted it the "Golden Yellow" that it is today.
2016: Switched from the Camaro to autocrossing the Miata in ES with mostly stock/unknown components
2017: Killed the second 1.6, Purchased a temporary NA8 Miata for the year... (also picked up a TCM Hardtop for it)
2018: 1.8 BP4W swapped the NA, brought the TCM hardtop from the Black NA, and moved to SC
2019: Bought a house, found out there was little to no autocross near me, so the car mostly became a weekend toy with a new set of wheels and the TCM hardtop.
2020: Continued as weekend toy, added the sidestripe and other small maintenance along the way
2021: Found out there were a couple autocross sites nearby, as well as finding out that trackdays were now within my budget, so this is the year the Miata really became fun again. Picked up some Supermiata Xidas, DIY a basic spoiler with extension for autocross, as well as some 15x9 wheels with 225 RS4s and Supermiatas BX11 wilwood kit.
2022: First "full year" of NASA DE, with a few other events throughout. Mostly a year of learning about aero and wanting to try some different things out on a budget. Added the Racebred front splitter, used APR GTC-200 rear wing, as well as a DIY diffuser.
2023: With no good reason, I decided I was tired of 100whp after all these years, and decided to toss the TDR Rotrex kit on, a 3.9 Torsen, as well as some sideskirts and fender vents. Quickly learned this year how hot the brakes get with the extra pace as well as how fun it is to keep boosted Miatas cool on track in the south.
2024: Finished up a lot of the 3D printed bits that I started at the end of 2023. Front air dam, ducting to the intercooler as well as two oil coolers (engine and Rotrex), quad taillights, hood vent inserts, and a new wing based on the MSHD air foil for improvements over the APR. Added in some other cooler improvements as well as BroFab AFCO brakes. Also went up to some 15x10 wheels and a few other changes when running in NASA TT4 trim. Last but not least, tossed a cage in the car for the amount of track time and limited street use it seems nowadays.
Welcome! I love this car, funny enough I don't remember where I've seen this thing, but I've seen it, and really love the color/bumper/aero. What bumper is that?
Welcome! I love this car, funny enough I don't remember where I've seen this thing, but I've seen it, and really love the color/bumper/aero. What bumper is that?
Thanks! It's one of the many printed bits on the car that I've made, so "OEM" (Oldham Engineering & Motorsports). I'll make a post about it and the process later as I'm working on a revised version specifically for NBs next.
Awesome, I really dig it. While the trash can bumpers are proven, they sure are ugly. That looks great and aero wise fixes the underbite. Any interest in producing those to sell?
Awesome, I really dig it. While the trash can bumpers are proven, they sure are ugly. That looks great and aero wise fixes the underbite. Any interest in producing those to sell?
Yeah, that's the plan with the revised version. It should make good use of NASA rules, and a mold to make sold copies for others more affordable.
A little re-cap on the bumper/air dam with other larger 3D printed bits to catch things up-to-date going forward.
Modeled all the bits in Fusion360, and scanned the existing components, mounting surfaces, etc with Revopoint scanners. Ducting goes back to the intercooler, then traditional plastic sheet construction between the intercooler and radiator still for now. TDR oil cooler mounts on the sides for engine oil and the Rotrex oil. These are 3" sized ducts that can easily be used for brake ducting if not using the side coolers. Hood vents using the Spiked vent shape, but were redesigned and color matched. Wing was an upgrade over the used APR air foil using an MSHD foil shape and sized to somewhat fit between NASA and SCCA rulesets. All parts to date are generally printed in ASA, assembled, epoxied, and prepped for paint. In the future, the plan for the air dam and some other parts is to make a mold and swap to fiberglass/composites.
Oh man this is so rad, after GWR posted a pic of your car in the 15x10 wheel thread I spent a good hour on google images trying to suss out what bumper that is lol. Bravo, def interested in purchasing a production one someday
Going to try and stick with a monthly update of this build thread, will capture my other Miata related projects through here as well.
January was a bit quiet on my Miata. New PB at Roebling, slowly feeling out the new springs (1100/500) on the rebuilt Xidas. Still working on the on the door card inserts to finish off the interior again with the cage in place. Should be finished up with the door cards in the next month or two. Checked off the MSF Level 2 Instructor Clinic with Turn One and almost have the NB bumper ready for the negative mold!
This car is awesome! Bonus points for the Rotrex. I loved the feeling of the Rotrexed NC I drove years back. Power increasing as you rev all the way to the limiter is just fun.
Ooh, dunno how I missed this thread! Subbed as well. Been following along on IG for a bit too. Stoked to see the front ends come to fruition for other NA/NB guys.
Golden Yellow TT4 Rotrex Build
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