HI guys,
I have a 2003 impreza type uk running 341bhp and 441nm torpue from the following modifications.
K+N Typhoon intake
Hyperflow TMIC
Forge BOV
3" Afterburner vortex system
Prodrive Cat
Tractive exhaust manifold
Tek 3 remap
255lph fuel pump
I would like to get about 400bhp reliably out of it for road use and the odd spirited trackday. I've been advised on a few options, I know I will need to uprate the turbo and the injectors, any advise on these is much appreciated.
However its the engine options i'm stuck on,
1 Swap my own engine for a new EJ20 spec C engine, i've been told these will run 400bhp happily.
2 Swap to an EJ257 bottom end ( told it can handle 400BHp )
3 Swap to an EJ257 bottom end with uprated internals ( told it can't handle 400BHP )
4 Uprate my own current bottom end,
Any advise much appreciated, I would prefer to swap either the engine or the block as I can make a few pennies back off my engine and turbo.

Cheers from ross

 

From what I know, which isnt much 2.5 bottom end will get you the torque levels.
Looking at your option 3, for 400 bhp I would have thought that uprated internals on the 2.5 or even 2.0 would be the best option especially if your doing track days. Also, I think a front mount would be needed. Consider an uprated oil pump also. If yours hasn't got the 6 speed box then that mite also have to be considered.

 

I'd go for a 2.5 with uprated pistons myself. However, if you do this, you may need to consider an uprated gearbox as well, as a 2.5 will generally make significantly more torque (which kills boxes).

What turbo and injectors are you running at the moment and what are you planning on running?

Oh and also, is it an STI or a WRX? If it's an STI you should be fine at 400bhp, as far as I know (engine + gearbox)

 

Some info from a man in the know:

STI: AndyForrestPerformance
WRX: AndyForrestPerformance

 

HI guys

thanks for the advice so far, the car is an sti an as for the transmission its fitted with an uprated exedy clutch. I'm currently running the standard newage sti turbo and injectors. Any ideas for good turbo and injector upgrades.

cheers from ross

 

Newage Sti engines are capable of handling 400bhp and so is the STI intercooler.
All you need is an MD321H turbo and probably a set of 650cc injectors to be on the safe side.

An engine swap is not needed but if you really want to do one i'd go for (i am in the process of doing actually) option 3, but then go for the slightly bigger MD321T which will give you around 450bhp and 450+BL/ft