Hi all! I'm brand new to the club and I currently daily drive a Scion FR-S but one of my dream cars is an Evo X. Id like to build it up over time but am wondering what I should look for when searching on the market.

Anything from a '11-'14 GSR is ideal but not a necessity. I'd love to build the motor (possibly bore it with upgraded internals), add E85 and a twin scroll that will allow for quicker peak boost times and potential for around 450AWHP. I would eventually beef up the trans and t-case for longevity.

Are these reasonable expectations and things I can look for in the used market? I'd love to hear your input and talk cars.

Thanks
-Kevin

 

if you are looking at 450 WHP, I think a built motor is overkill. I think there are plenty of builds with just a turbo swap and E85 with supporting mods that will get you similar numbers.

Of course, you can over build it for future growth which is never a bad thing. Unless you are trying to launch your car from light to light every where you go, GSR trans are pretty stout.

 

- Stock turbo / manifold is twin scroll
- Stock motor is fine for 450whp
- Stock turbo is good for 350-380whp
- Simple stock frame (OEM turbine/compressor housing) upgraded turbo will give you 450whp
- OEM t-case and transmission is just fine for 450whp unless you want to launch 10x a day for 365 days.

 

With what I bolded in your post being said, is 400whp with e85 stock turbo pushing it too far?

 

Without having any dyno data in front of me just knowing the engineering of them, I'd say to get the boost you'd need to do that the turbo inlet to compressor radius is too much of a flow restrictor.
If you want to run E85 either port, polish and upgrade the turbo internals or upgrade the turbo size. With the former you'll get the power and quicker spool. With the latter you'll get better power potential with similar spool to stock.
Someone with real world experience should give their opinion before taking mine as fact though.

 

I have no doubts the stock drivetrain is robust and can handle up to 500 ft-lb of torque, however the turbo lag associated with those kind of numbers on the stock frame turbo would be abysmal (for me). I'd like to have as quick of a spool as possible at a power rating of around 450 which becomes quite the balancing act between boost pressure and turbo size. An easy way to do this is to increase displacement and run E85. So if I increase bore, might as well build up the engine. (I'd rather increase bore because I love RPM.)

Speaking to the trans, I'd rebuild that for the strength as well as changing the final drive (the Jacks build) to be geared for higher speed due to the increased output of the engine. Plus I'm a child and launches are fun.

-Kevin

 

I have a stock frame turbo. The turbo lag is very minimal. It comes on a little later than the stock turbo, but I can't tell much of a difference. I'm running a 3576r and I'm laying down around 465whp 375tq on pump gas 93. I'm going to flex fuel in a month or so and that will take me to 500whp and 400tq. Motor is pretty good stock, just keep the torque to 400 or less.

 

as already mentioned above, with stock frame turbos, you probably lose about 500 RPM. maybe just build the motor and head to rev to 9K instead of boring out the engine? I mean larger displacement is always welcome but that seems like a lot of work and money for 450 WHP that can be done on a stock engine.

Again, may be you are just over doing it for future growth which is

 

why? the stock GSR transmission is very strong - Jacks produces top notch stuff and if mine ever blows then that's where I'm going to send it... but "rebuilding for S&Gs just to be safe" isn't necessary. If you're planning on launching this thing to the moon, then you should be more concerned with flywheel/clutch durability.


Changing to the 4.23 final would really tone the car down in a way I don't think you'll like unless you have big power. It kind of puts cars 400whp and below on Ritalin. Personally, I enjoy the gearing the way it is and most likely after owning one for a bit you'll appreciate it too.


-asher