New here - Colorado EFR track build
 

Hi everyone!

I'm in Colorado and I'm working on an EFR track build. I got a killer deal on an '95 NA8 R-Package '95 Miata a few years ago with the only drawback being extremely high miles (250k+), which hasn't proven to be an issue at all.

The car is currently set up as a mild weekend track day build - Hard Dog bar, Sparco seats, harnesses, to-be-delivered OEM hardtop sourced from a friend in Canada (where they're a LOT cheaper!), 949/Supermiata Xidas, FM sway bars, once over on worn suspension components.

I've pretty much dialed in my lap times at the local track (High Plains) on this build (lap-to-lap and theoretical lap to best lap data comparison). Which means it's time to ADD POWER.

My goals are modest power with good transient response and the highest reliability I can muster. I'm not looking to class anywhere specific although I will probably eventually run NASA TT semi-competitively wherever I land.

Here's my current parts list:

Kraken full exhaust side
EFR 6258 with EFR wastegate actuator and recirc valve
MS3PNP Pro
FF640 injectors
IGN-1A coils
AEM X Series Wideband
Supermiata coolant reroute
Supermiata crossflow radiator
Fab9 Intercooler
??? boost piping. Trying to decide between adapting coupler/prefab (eBay style), FM silicone hoses, or welded tubing (I can MIG weld decently and could probably do thin-wall steel OK, but it would be a process vs. something prefabbed).
??? clutch. Have not made a decision here yet.

I have tuned a lot of more "modern" torque-model systems (ME7, Simos18 in Golf R) and helped a friend with an E30 Megasquirt build so I have some experience tuning and look forward to playing with the MS3PNP.

I'm doing my build in phases to reduce risk and let me troubleshoot at each step:

1) Engine once-over/refresh and cooling update. Coolant flow reroute kit and crossflow radiator, and maintenance (timing belt / water pump, every seal I can get to as part of the TB job). Compression and leakdown test well. No observed blowby as an NA car so we'll see.
2) MSPNP3 Pro on stock setup.
3) IGN-1A and sequential ignition wiring on NA.
4) Kraken exhaust side, EFR6258, Fab9 Stage1 Intercooler, FF640 injectors.
5) Replace what breaks, starting with the clutch and then seeing how the tired old engine does. If it gives out I'll do a built bottom end.
6) Chassis reinforcement and eventually aero.

Please let me know if you have any feedback on my build - opinions on boost piping options and clutches appreciated (I think I'm going to go FM1 for clutch based on what I've read here, but I'm happy to listen!).

Look forward to posting more!

-

Brian

Welcome to the forum you should k swap.

Lol. Quitter.

Welcome to The Forum. There are quite a few of us here that track our turbo Miatas. Heat management ends up being the biggest issue we fight.

As far as the forum knows i have a 1.8 VVT build and a EFR 7163 Twin Scroll in the works :giggle:

I'm hoping the Supermiata crossflow and coolant reroute will be sufficient to keep me cool. With the thin air and 95+ summer temps at the track, I'm sure I'll be pushing it. I run the stock undertray (of course) but haven't done any ducting yet - is the general consensus that additional ducting is a must or can it wait until I do the math and work through a full aero package?

The Supermiata crossflow doesn't cut it for me on the street. I am ducted. Colorado is a bitch.

I assume A/C and no hood vents?

FM crossflow + Stage 2 fan kit doesn't cut it on the street either. My car will eventually hit 230 in non moving traffic with AC on. I will be moving to a TSE radiator and single spal and if I cant sit in traffic with the ac on as long as I want with that setup I give up.

No AC, Rtheory hood vents. Reroute, ducted, single stock fan, 13 row oil cooler.

I also have 2 A/A and a compound turbo-super setup, so 1/2 of the radiator has 2 heat exchangers in front of it. The other half has its own dedicated airflow. The oil cooler also has dedicated airflow.

Colorado has about a 15% cooling efficiency hit. It takes a lot more effort to generate power as well. Higher power local cars struggle with heat at the track. My car isn't a track car, but I regularly push 250lbft + uncorrected above 2800RPM. The power is seamless, so I spend quite a bit of time with positive manifold pressure during normal driving.

Summer days here frequently have ambient temps of 95+F. I have no heat issues when ambient temps are below 80 F.

I love the SM radiator, it is a quality part and the fitment is fantastic. Something larger is going to be a headache, I will have to do a fair amount of redesign and fab work to make it fit.

I made a flat undertray from 3/8" plywood going from my GV lip back to the area just in front of the transmission - resolved a lot of my heating issues. Hook it inside the bottom lip of the lip (heh) and screw it down together, add a few bolts into riv-nuts in the back.

Solid build plan.

My 6258 with medium boost spring yields 10-11psi wastegate only.
Which is 250hp and I think 225tq.

This was enough to shear the teeth of my 5spd 3rd gear, during a track day.

You might be ok with a non vvt na 1.8 though on wastegate only at the track.

What trans on this build? Hoping at least an AZ6. BMW Getrag from KMiata ideally.