will_wrx

Is this possible? and is it worth doing? What power can the internals take?

Or is it better to go for aftermarket internals?

Cheers

TonyBurns

iTrader: (3)

If your going to put new age STI 2ltr rods and pistons in then I would bin the crank and bearings and upgrade to the twin scroll crank which is cross drilled and nitrided (better oil distribution to the bearings) and some acl bearings, but it all depends on what power your going for? as those will run 400bhp all day long, if your going for 450bhp then I would be looking at new pistons and rods, actually anything over about 400bhp and id be looking at new pistons and rods, these are not exactly expensive

Tony

will_wrx

Ahh I assumed with the STi7 internals apparently being forged, these might be as good as aftermarket parts.

I want 400-450 when the car is finished. I'm building the car up at the minute but still using stock motor. I plan on building a 2.0CDB while I build the chassis so I can keep the car on the road whilst I build the motor.

I am going to spec turbo/injectors etc after I've built the motor as its going to be a long ish project as I'm doing all the work to the car myself and still learning.

But what crank would suit me best, thats something I know nothing about. Would it be worthwhile going for twin scroll crank? or Newage STi crank? Classic STi crank? I'm guessing because I'm going for 400-450bhp an aftermarket crank would just be overkill and a waste of money?

Thanks

TonyBurns

iTrader: (3)

The twin scroll crank (JDM STI 2003 onwards) is that one you see advertised as being cross drilled and nitrided, its the best one out there for subaru's plus you can run 450bhp on the new age STI rods, how long they will last is another matter, hence if your going for 450bhp then your better off with after market parts for security

Tony

will_wrx

Awesome, I need to find me a twin scroll crank!

Thanks for your help mate

BlueBugEye

iTrader: (12)

Sorry to Hijack but I'm on a similar mission - currently I have a 2002 WRX but have sorted the suspension, styling and brakes so don't want to start again - have the offer of a Closed Deck 2.2 for a good price what heads to go for is my question, I know V5 will fit if I change the inlet manifold but could I go STi Newage V7/V8 on my ecu? or would the AVACS mess it up and mean I needed aftermarket ECU?

will_wrx

As far as I know, using the AVACS heads is a mission. I read it somewhere.

I'm not very clued up but as far as I know, STi ECU or Aftermarket is the only way to go

Hope you get it sorted mate

dazdavies

iTrader: (22)

Bit of misinformation there. Buying a twinscroll crank is bit necessary IMO. Yes the cross drilling provides slightly better lubrication but the standard crank will be fine so spend the money for that elsewhere.

Don't forget that the none forged, none cross drilled 2.5 crank has more than proven itself in several well known 2.3 and 2.5 builds that are in excess of 700bhp!!

I dare say the standard crank will be fine for your application.

pistol

let me know when you wana sell your engine bud, as im in northants aswell!!