hi peeps, i am looking into buying a 2005 05 or 55 reg sti blobeye. i have plans of running 450 bhp on standard internals and have heard that the sti engines have seemed to cope with them. i have also heard that the MY05 sti engines have generic pistons instead of the sti forged item and are therefore weaker. i would like to know how much weaker they are. also would the 55 also have the pistons.

 

The 2.5's have the dodgy pistons not the 2ltr engines, 450bhp, well its the drivability that your going to lose low down, the bigger the turbo on a lower capacity engine, the greater the lag you will suffer, you will also need to go fmic and probably need to upgrade the clutch.
I would have a look at how well a 400bhp car drives if your going to use the car as a daily driver.

Tony

 

Suggest you speak to David at Api mate.

"Seeming to cope" and "definitely reliable" are different matters.

Whenever someone is thinking of tuning, they need to first ask:

"How much can I afford"

That is the biggest contstraint on whether you can have what you want.

I would suggest that 450bhp on a 05 STi would be very unwise and to get to a spec that is properly bullet proof at that level, you'd be looking at a big expenditure, probably as much as a 2.5 450bhp + conversion which would be better than the 2.0 litre owing to the bigger capacity providing more torque and better spool characterisitics for the kind of turbo you need to push sufficient air to get that figure!

Settling for nearer 400bhp on a JDM twin scroll STi impreza might be your best bet.