Ok how much can your standard engine safely take before you start blowing head gaskets etc .The car is only going to be thrashed now and again its not gona be used on track,however i would like to be able to open it up without fear of things goin wrong.I am hoping for close to 400bhp eventually.If things do need changing what upgrades will the engine need to take it .
2003 sti ppp.

 

You can run 400bhp on that engine as long as its in good working order (well maintained etc) quite happily with the supporting mods (turbo upgrade, injectors, fuel pump, remap etc).

Tony

 

Cheers Tony, it is maintained to the max by myself so happy days.

 

As tony says with the correct mods and good re-map you'll be fine. STi's are alot stronger than the uk chocolate engines! I know a couple of peoplle running 400-420bhp as there every day runner.

 

Agree.
Mid 400s ok on them

 

running 445 on my 04Sti.
Standard internals.

And it's had a pretty good thrashing lately!

 

I'm running 432bhp on MY03 STi, mapped by JGM himself.

 

Cheers guys ,just wondering to get this sort of power do you have to suffer more lag, anyone managed this without using tubular headers.What turbos do you have.

 

I am using tubular headers, but I fitted them after I didnt acheive 300lb ft torque with a turbo back system and remap.

I am using the MD321T with STi 8 top mount and lag is minimal and not that much more than the standard VF imo. I cant see why ppl always talk about lag cause you would'nt stay a high gear to overtake! Drop a cog and your away.

 

I have just removed my (unequal)tubular headers and gone back to standard headers and decat uppipe all preped by harvey the sound is phenominal the tubulars dont sound as good.Its a compromise but the proper burble is back and its awsome.

 

Harveys ported are good for up to 400bhp I believe. Over that I think you should really use tubular.
See my garage for my spec