Hey does the STI have stronger internals than the wrx? (i would think so) just trying to clarify this.
i would think the rods and what not were designed a bit more heavy duty than the wrx, but i am not 100%

if the STI has stronger internals, what about them is stronger?

-greg

 

IIRC, the USDM and JDM internals are both forged, where the WRX are cast?

Krinkov, Moike, one of you guys want to chime in?

 

do you know if the 2006 2.5L wrx is essentially the same internals as the previous years wrx? meaning non-forged.. same materials.

thanks

 

i don't think the USDM 2.5L STI is forged at all. altho i'm hearing that the rods are forged only. if the USDM STI's internals were forged i would think that, when pushing over 400AWHP, wouldn't be a concern on reliability.

 

forged rods and cranck, Hypereutectic pistons. Hypereutectic pistons work excellent when used at the stress levels they were designed for, but when pushed harder they dont provide the det resistance of forged pistons. Though I was pushing upwards of 340whp on Gruppe-s dyno with my GT30 for 40K+ miles on a stock bottom end with no problems at all so take that fwiw

 

Was your boost level around 18-19 psi ? Any detonation ?

 

yeah on 91oct mike had me tuned at 18.5psi, no det and I run a knock-link too so I would see it. Now that its back to stock with the old pre-reflash stock map my knock link goes off all the time!

 

Thanks for the response . I'm thinking of adding a knock-link to gt-30r set-up , to catch detonation running at 19 psi . Thought about a smc alcohol system but , decided not to go with it too much to worry about .