burt2000

iTrader: (1)

just wondering what sort of bhp people with uk spec imprezas are running with standard internals, when does it start to get a bit dodgy? would say 340bhp be ok with all the proper supporting mods and really well set up or is that pushing it a bit

any replies appreciated

Barry

haroldhettaturbo

iTrader: (2)

When i spoke to Andy at the clinic, he advised me not to go past 330 on the standard internals.

He said he does no classics running 380 bhp on standard internals but wouldnt advise it.

gunna get mine mapped to around 320

Dave

burt2000

iTrader: (1)

yeah i think i will stay safe around the 320-330 mark myself the standard intercooler should still be ok also at this level shouldnt it?

am i right in thinking that the following should see around 320-330

full decat exhaust system(turbo back)
Greedy boost controller
Panel filter or induction kit
Walbro 255 fuel pump and rising rate fuel pressure regulator
TD05 16g front entry
and all remapped/set up

well this is what i plan to do anyway hoping i will see around that figure with the above mods

harvey

iTrader: (48)

I ran a M/Y 95 WRX Wagon at around 385 bhp for two years on standard internals and when I took it apart, ( not because of an engine issue) bearings, rods and pistons were in good fettle.
The block and crank are back in the car with other rods and pistons now making 422 bhp, perhaps more as of this Tuesday when I fit a Sigma/Simtek ECU and the original rods and pistons are now in another car at around 350 bhp.

rigga

iTrader: (4)

Its hard to put an absolute figure as it greatly depends on how the engine has been treated in its life.... a well cared for unit would stand a better chande of being upgraded to say 350 plus than one thats been ragged and not looked after.....some can do 400 a lot do a great deal less....

bryhp

trouble is with uk 99 engine the pistons are cast so not as good as imports, Change the pistons and internals if you want to go above 330BHP. Better still pick up a closed deck block and some v5/6 heads, and you will be able to run in excess of 400! as long as your gearbox is good and yo8u have right clutch

AlanG

Back in 2003 i ran a std '99 engine at 415bhp/352 Ib ft with no issues, this was at 1.4 bar boost on the turbo i had at the time on 98 RON fuel only.
350bhp is a walk in the park for a std internal engine imo and will provide planty of fun without worries. It all depends on how good the basic engine is, how well the mods are suited and fitted and how well mapped imo.

burt2000

iTrader: (1)

Cheers mates...the engine has 66k on it and according to the service book been serviced every 5k by subaru and i recently got it serviced again when i bought it...all the work will be done by OMA tuning here in belfast and he is very well known for making fast scoobies and has a great rep with them so all the parts used will be very good and should be well set up and mapped...

is it safe to use the standard inercooler for upto 340? also can the standard gearbox and clutch hold out to that...i wouldnt be launching it off the lights anything as i dont like to abuse the car but the extra bhp would be nice and make it pretty sharp id think....enough to see off the likes of an fq340 or similar lol, scoobies are lighter too :-)

harvey

iTrader: (48)

This business about closed deck blocks to get 400 bhp is total bollocks. The Classic Subaru block is good for a long way past 500 bhp as many people have proven.
I thought O/E Cassic WRX pistons were cast. Are they not?
Barry : If your car is M/Y 1999 it should have a TY754 gearbox and not TY752 which is much weaker. Look on your VIN plate on the passenger side suspension turret for the TY number. It depends how the box is treated but lots of these UK TY 754 run in the high 300s without any apparent problem.
At 340 bhp your TMIC will be struggling. I have an STi 3, currently 335 bhp and it is not too difficult to get the induction temperature beyond 70 deg C.
Look in Technical General and you will find a thread "Intercoolers" which has a lot of info. Bear in mind that I am referring to Classics and not STi 8 onwards.

Steve Whitehorn

iTrader: (13)

Harvey
Do you know what year the TY 754 was introduced?
Cheers
Steve

terzo282

i was advised not to go beyond 330 bhp on a uk engine ,basically to give the engine some sort of longjevity . yer i reckon that they would take more power but do you really want to build a time bomb.

this info was given to me by paul at zen performance and tsl motorsport and i reckon they both know what they are talking about

Tidgy

think 350 is max on most, yeah you might find odd ones that will go higher, but i've also heard of 320bhp being to much for some engines.

personally id get the mapper to take it to the point he's happy with the firgures and performance he's got and then back it off a bit and see what happens.

unless of of course you have money for a rebuild if it goes pop, which if you have may as well just have it rebuilt anyway with uprated internals

burt2000

iTrader: (1)

yeah i think a nice safe 320-330 will do me, ive never been in one with that sort of power but im sure it will be quick enough for road use as its 100+ bhp over standard. it also means i wont have to upgrade anything else like gearbox or run a FMIC...and i def dont have lots of money so i want to keep it safe and prolong the engines life

harvey

iTrader: (48)

The TY754 gearbox was fitted to version 5 cars onwards ie. 1999.

Dan 2

iTrader: (2)

Hi Harvey..

What Gearbox would you recommend as a replacement for the UK 99 car if running between 310-350 bhp ?

ZEN Performance

330bhp, or call it 340 if you manage it is a nice safe level for a UK engine. You can make more, it might last well, or it might grenade itself due to a variety of factors not exclude just plain old bad luck.

If you want 400 odd hp, with a daily driver, and don't have the luxury of constant monitoring, tinkering or fancy fuel, a better engine is advised.

Like all these discussions, I am not saying you can't go for high HP on a standard engine, just be aware of the risks. I have had people dissapointed at an untimely engine failure, who were firmly of the belief that 400hp was fine for all UK engines because they had "read it on scoobynet".

But for car in question, 330-340hp, or in other words about the sensible limit of the OE gearbox, injectors, clutch, intercooler and sensibly priced turbos, is a good place to be.

paul

RaymondH

I agree. I spent a lot of money fitting all the right bits (but still with standard internals) and have 325bhp @ 1 bar and 385bhp @ 1.4 bar. I run the low setting 90% of the time - it's more than enough for road use

Aztec Performance Ltd

iTrader: (234)

When you're increasing the factory output by over 50%, you can't expect it to be 100% safe. Like Paul said, it could last or it could go pop.

I have been running 340/340 for a while now and the engine has coped fine. I don't expect it to last as long as it would have done left standard. Don't overlook the gearbox though...can be just as costly as an engine going bang. My gearbox (TY754) gave up quite quickly.

I would add an STi7/8 TMIC to the list and possibly some headers.

burt2000

iTrader: (1)

lol yeah ill have to be sensible with this one, as first off im not on a huge budget and more importantly i want to keep the car safe....the subaru is more of a weekend / evening car as i have a smaller car for work and the high miles. looks like 330 is the way to go then and id say i will be pretty impressed with that on the road, can the standard 440 injectors cope with that or should they also be uprated with the walbro fuel pump and FPR, id prob put and sti7/8 top mount on too just for good measure

harvey

iTrader: (48)

If you can afford it then go for a Possum Bourne gearkit, synchro helical for a road car or see what is available from the likes of PPG or Modena. I think the kit will cost around 2k from P.B.
A cheaper alternative would be a five speed box from a New Age WRX but providing you are not doing drag starts your TY754VN??? should be capable of handling 350 bhp.

H4RDY-P1

iTrader: (46)

Sorry to hijack the thread but what do you guys reckon a freshly built P1 engine will be ok at? I recently just had it mapped and it made 347bhp with a vf 35,fmic etc, with loads of surge so im not happy and thinkin of fitttin a bigger turbo,wot you think, harvy?