henrysmith

iTrader: (5)

Trying to find out who's running what power on standard Hawk internals? Both WRX and STI internals and WRX gearbox? Also how long have you been running and with any problems?

Running a SC42/STI TMIC on my GB270 and de-tuned to run 363BHP/321lbft - always planned on a forged build with the SC42 but wondering about having it remapped to see mainly higher torque.

I know all about the weakness of the internals and wrx gearbox but recently spoke to a guy with a Hawk WRX running 400/400 (with dyno sheet) for almost 4 years and 45000 miles with seemingly no problems - anyone else running similar levels for similar times? This was on a STI TMIC as well.

the_baz

I'm running 350 bhp and 350 torque I've had the car 6 months and brought it like this

legb4rsk

just look for people who look like this.


http://www.google.co.uk/imgres?q=ner...9,r:2,s:0,i:92

stevie1982

iTrader: (16)

Brilliant that did make me chuckle.

To the OP, run as much power as you're willing to but just keep in mind that at any point it may go pop and in most cases it will cost more to put right once it has. So I guess its your call but I would rather peace of mind and the cost be as low as possible.

tubbytommy

iTrader: (20)

i think your approaching the limit, but how you drive it would contribute to how long it lasts also.

jazzyjembreaze

iTrader: (11)

was running 375 with ecutek full decat harvey headers & uppipe walbro ,plugs , filter
headgasket failed ,,
personally i think if you break the 300 its a ticking time bomb

fully forged uprated studs ,pumps, bearings etc etc makes it a different engine for sure

leecalcars

iTrader: (37)

Running 360/430 on 2.5 Sti standered in a classic

henrysmith

iTrader: (5)

As original post have always been planning on a forged build etc but this will probably be middle/end of next year now if at all. Looking at a second car (again) purely for fun/weekends as an alternative, so might leave the forged build until/if the engine goes.

I have now seen a few people who have been running around the 400/400 mark, some with 2.5 WRX's and some with STI's (removing the gearbox issue).

So I'm really trying to justify having the car remapped to around the 380/380 mark and see how it lasts and trying to find out if other people have done this and how long the engine/gearbox lasts.

chopperman

I ran 360/440 for about 4 months, then piston #4 and #2 decided they had had enough. Was a good excuse to get forged
I think there could have been some ring-land cracks before i had it mapped though as it did smoke on start up sometimes.

New_scooby_04

iTrader: (4)

Boost is the limiting factor with the std Hawk pistons, anything above 1.35 ish and the ring lands are likely to let go!

Realistically, if you're going for anymore than the exhaust/filter/remap route on the Hawk (which should get you around 350bhp and 380 ft lbs and spool from nothing) it's a good idea to get the pistons replaced.

Making a power figure is one thing, sustaining it reliably is quite another!! Anyone who has got a genuine 400 (and uses it) for any period on the Hawk is the exception rather than the rule IMHO

WRX Blues

Running 358bhp / 380lb/ft with filter, PPP and remap only - HG started failing pretty much immediately after re-map. Now replaced with Cosworth HG and ARP studs - let's see how we get on...

WRX Blues

Should have added that max boost is around 1.35 bar.

chopperman

Didn't you put forged pistons in at the same time ?

ad172

Was running 385/410 on standard. Car is currently in having uprated Head Gasket and Head Stud kit due to early signs of HGF. Also plan to get the boost turned down as I believe this may be the main cause to the failure.

Chopperman as for getting Forged pistons dropped in at the same time, to do this properly you have to get the piston chamber honed otherwise you will be using a lot of oil. To do this the block needs to be split which involves a large expense/labour and you just as well forge the lot!!!

Tomwrx

iTrader: (54)

i was running 355bhp and 353 lb/ft on my hawk wrx for 12months then the 5spd front diff started squeeling like a bitch so 6spd fired in and been running 355bhp and just over 400lb/ft.
total of 2yrs + at that power,cars in getting a few things added and will be getting maxed out to see what it can take,
turbo is vf43 and completely standard internals.

im planning on forge build next yr and going for 450-470 but not much more as i still want to use it as a daily driver

WRX Blues

Probabaly should have done but don't plan on taking beyond current map which peaks at 1.35bar and then tapers off...

eggy790

iTrader: (20)

arnt hawk wrx and sti internals the same? just the heads that are different?

chopperman

I think the block and maybe pistons are different.
I think the WRX uses an ej 255 open deck block while the STi uses the ej257 semi closed deck block. I believe the piston tops are a different shape as well.

moneys

iTrader: (5)

my hawk runs 350 hp and 365 lbft. had it for just over 3 months, HG has just gone, when i checked the paperwork it had had a replacement one 20k ago as well, looks like they just put the standard gasket in, this time im getting the cosworth one, i cant afford to go forged and ive been reliably informed the uprated gasket will solve the hg issue, so fingers crossed, good thing is he is going to do my clutch whilst its out, doesnt need it but i aint sitting around waiting for that to go as the car has now done 62k on a standard sti clutch.

I may look into getting my map tweeked to try to avoid and ring land issues in the future, plus I like the sounds of these duel maps

New_scooby_04

iTrader: (4)

I'd get beefier studs whilst you're at it if I were you, I doubt the uprated HG will sort it by itself without better clamping from beefier studs!

ad172

Are you having uprated head stud as well? Certainly a worthy upgrade at this stage. I think ARP are regarded quite well.

Adam

moneys

iTrader: (5)

The bloke who is working on my car said its only worth going for them if I go big power, I'm not going big power, I'm happy as it is.

Is this right? Ive been hit with an unexpected 900 bill so don't want to spend money if I don't need to

DT-SPD

iTrader: (7)

Threads like this always make me nervous about my cars engine. It seems that 1.35bar is a known safe max on std pistons. I had mine remapped by a mobile mapper and he set it to 1.45bar !!!! So pleased I have now redone it myself and set it to 1.3bar, also improved the drivability a lot too.

fpan

iTrader: (11)

As others have said I doubt teh HG is the cause.
Get some ARP bolts.
What boost are you running?
Anything mroe than 1.3-1.35 and it's a ticking time bomb.
I think a lot of these failures depend on the driving style too.

ad172

The Head bolts should be replaced as a matter of course, regardless if you uprate them or not. I'm sure someone far more technical than myself will confirm they are stretch bolts and should not be re-used. On that basis for the sake of a few extra pounds (10's not 100's) it is absolutely worth using up rated Head Studs.

Adam

New_scooby_04

iTrader: (4)

What he said! I would suggest that if you don't have them done you may well be back at square one before long and given that it's not much more money to upgrade to something like the cosworth 11mm set, it's a no brainer!

tubbytommy

iTrader: (20)

you remapped your car yourself???

DT-SPD

iTrader: (7)

Yeah.

moneys

iTrader: (5)

called the garage and told him to upgrade the bolts then as well

chopperman

Very wise to replace the std head bolts with 11mm head studs. I have ARP studs in mine