E85 Build? Anything I'm overlooking?
 

So, I picked up my 1990 Miata about a month ago, and have been working on it since, trying to get it back up to par (re-installed PS, fixed a coupe cooling issues, new tires/brake pads/rebuilt a couple of the calipers, a few new bushings here & there, changed a few fluids ect). At this point, the car has 129k miles on her, and appears to be running pretty strong for her age.

My goal with the car is to boost it lightly, and eventually the car will serve primarily as a track car/play toy. It will see quite a bit of autoX duty as well as full road courses (mostly HPR & PMP). The suspension is fairly well sorted out for the moment, so I'm going to concentrate on power for now, as she is sorely lacking in that department haha! The only mods at this point are a foam-style filtered intake, plug wires & Magnaflow exhaust that the previous owner put on the car.

Either way, the plan is to run a compressor around the size of a GT2554/60, pushing around 10-12psi. This will likely be done in stages, picking up parts in the following order:

- MegaSquirt of some type (MSPNP or DIYPNP) along with GM IAT & WBO2. At that point, get used to playing with the MS in N/A trim.

- New/upgraded clutch/flywheel (thinking about FM's clutch happy meal w/10 lbs flywheel).

- Injectors & fuel pump. Likely Deatschwerks 800cc modded stockers & their 300lph fuel pump, unless anyone else has any other recommendations? I know the 800's sound excessive, but for a 25-30lb/min compressor on E85, I was thinking I might run out of overhead with your average 550cc injectors. At this point, I would likely convert/tune to car to E85 in N/A trim/scale the injectors, tune a base fuel map, ect.

- Pickup a turbo kit, likely something running a GT2554/GT2560 or maybe a knockoff Mitsu/IHI equivalent if the price was right, but I would prefer to have the responsiveness of a Garrett GT-series snail on the street. Car would be tuned on E85 around the 10-12psi mark likely.


The biggest appealing factor for running E85, is I've ran it in the past on my previous STI for about ~1.5 years, as well as played with a few other E85 tuned Subaru's/EVO's, and it's hard to get a car to knock running the corn gas, and allows a person to tune based on the torque curve rather than the knock threshold, which is appealing. The reduction in EGT's/cooling effect is useful, especially on a car that should see a lot of track duty.

So, while I'm familiar with running ethanol on a daily driver in the past (my Miata is NOT going to be my daily driver), at the same time, it was on a car that was considerably newer (1990 vs 2006), and while I never had any corrosion issues on my STI, at the same time, I'm wondering if anyone else has ran into any issues with corroding fuel lines/tank on the older NA Miata's?

I'm assuming after the conversion I'll have to change the fuel filter a couple times within the first month or so (cleaning effects of ethanol "cleaning" the debris off the fuel tank), but beyond that, anyone having any fuel line related issues running E85 on these cars that I should be aware of? In the Subaru world, it's common to merely run bigger injectors, a Walbro FP and call it a day, but figured I would ask.

Is there anything else (chassis/motor specific) I should consider prior to making the swap? Any major parts I've overlooked (didn't mention turbo components individually, but we're talking turbo/piping/FMIC/ect)?

Any feedback would be greatly appreciated!

Thanks in advance!

-Brandon