300whp build
 

I'll just say beforehand that I know I could've gone with a 1.8 but I already built the motor.
I have:
ported 1.6 head
Titanium valve springs and retainers
Wiseco pistons
Carillo H-rods
rebuilt with FM kit
used the FM 2 turbo kit as my base swapped out the 2560 with a Gen 2 gt2867
​Xidas big grip kit from super miata 700/400 rate
ms3 pnp
Welded torsen 3.96 rear diff
Dw300 fuel pump(plan to run flex fuel when I turn the boost up)
​FM coolant reroute
FM crossflow radiator
FM stage 2 brushless fans
ID1050cc sequential injected
ls2 coils with sequential firing
fm stage 2 clutch and flywheel
fd rx7 alternator
and I don't have it yet but I'm still trying to source a 6 speed.
any suggestions for anything I missed or changes that I could make to help reach my goal. Again other than a 1.8 swap because again already built. I'm also thinking of getting a OS Giken lsd but haven't been able to find much about what the gearing with that would be like.

Do a 1.8 swap :rofl: Just kidding...

This thing is going to rip like hell on E85, even on a 1.6 motor. Spool will be 4k, but when it's on, it's on!

Gearing will be a little short with that much power, try to go 3.6 with a 6 speed

That's the plan. 3.6 sadly wasn't available when I was doing the torsen swap. I'll probably switch to a 3.6 later if I can find one and keep the housing so I don't have to reweld the housing

From what Ive seen a 5 speed running that much torque from a turbo is not long for this world, mines going out at about 220wtq. Reinforced diff housing with stiffer engine and diff mounts will probably be needed as well.

already tig welded 3/16" aluminum plates at the crumple point of the torsen and already aware of that. I'm still trying to source a 6speed before I turn the boost up. Where the 6 speed gets questionable after 350whp is why I'm only shooting for 300. Been looking for one for 2 months now with no luck. I was originally trying to source a t2 fc trans and was going to swap the bellhousings and make some aluminum brackets and a driveshaft but those are unicorn kinds of rare. Also my bad I forgot to put in I've made custom engine mounts and that I have the upgraded diff mounts from FM

You can run 350whp with a 6 speed on the street, you just have to keep torque peak at around 280ft lbs and try to hold it to the top, tapering boost and not go crazy in the midrange.
A good tuner and properly ported exhaust housing can do that. Remember: 350whp is only 260tq at 7200rpm.

+1

I currently have a TSE setup w/ a 6258 at 15psi w/ e55% on a NA 5 speed. I have boost slowly tapering in between 3000 and 4000 and so far so good. At one point i had it turned up to 17psi that would hit hard at approx 3300rpm but the torque hit definitely would have taken a toll on the trans if the tires didnt spin.