Subaru EJ25 Conversion Question

[hewlett]

Just bought a 95' Impreza with a recent EJ25 engine from an STi, with:
STI 2005 EJ25 ENGINE.
STI EJ25 OIL PUMP.
AUTOBAHN 88 FRONT MOUNTED INTERCOOLER.
KAKUMIE EXHAUST HEADER'S AND UP-PIPE.
3" TURBO BACK MONGOOSE STAINLESS EXHAUST SYSTEM WITH 5" SLASH CUT TAIL PIPE.
POWERTEC CONE FILTER.
WILSON POWER SILICONE HOSE KIT.
AP RACING 6 PAD, PADDLE CLUTCH AND FLYWHEEL.
PIGGY BACK ECU WITH SWITCHABLE BOOST SETTINGS, that's playing up!
WALBRO 255 LPH UPRATED IN-TANK FUEL PUMP.
4 POT SUBARU FRONT BRAKES FROM NEW MODEL IMPREZA.
EVO SPORT UPRATED DRILLED & GROOVED FRONT DISK'S WITH BLACK DIAMOND PADS.
17" MILLO MIGLIA ALLOY WHEELS WITH 4 GOOD TYRES.
TURBO BACK FULL DE-CAT STAINLESS STEEL 3" EXHAUST WITH 5" SLASH CUT TAILPIPE.
LARGER MODIFIED TD05-16G TURBO WHICH SPOOLS UP EXTRA QUICK.
VERSION 2 STI BOOT SPOILER WITH BUILT IN BRAKE LIGHT.
BAILEY'S ALLOY BLOW OFF VALVE.
GREEDY 2 STAGE BOOST CONTROLER.
GREEDY UPRATED FUEL REGULATOR.

...anyway, could anyone advice me what bhp/torque I can safely expect at maximum (safe) boost, once someone has sorted out my ecu issues (spluttering on boost, assume it's a set up problem)...thanx

[stevieb]

if the EJ25 is the new 2.5 conversion it will depend on what pistons you have in the engine build. if it is forged you could expect more tahn 400+ with correct ancillaries. but if it is standard STi pistons you would get more than 350, as the pistons are not as strong in the 2.5s and the older 2.0 litre cars. Newage 2.0 STis 03-05 cars could see anywhere upto 450hp on standard internals.

[Vixpy1]

Whats the Piggy back ECU, and is it attached to the 95 orig ecu, or a 2005 2.5 Sti ECU ?

[hewlett]

I'm sorry but I don't know. The above description is from the eBay ad and I looked at the ecu in the footwell and couldn't see a piggy back unit, nor tell if the ecu is original '95 spec or the 2.5 one..

[Vixpy1]

Is there a code on the ECU ?

[hewlett]

Hi, it says 7D in large type then AB730 and other numbers which I'll get if you need them, ta

[Vixpy1]

I can't remember off the top of my head, but will check it out by monday for you.

[hewlett]

More details: 226 AB 730 AI8 000D08
cheers

[hewlett]

Thanks a lot !

[hewlett]

I think I may have the answer, I found references to this ecu from a posting in 2004:

http://bbs.scoobynet.com/private-sale-car-parts-ac...

Looks like it's the original '95 ecu, I think.

[DocJock]

It looks like your limiting factor will be the turbo.
A 16G TD05 will flow enough air for 420ish BHP IIRC. After that it becomes an expensive hairdryer.

[Vixpy1]

hewlett said:

I think I may have the answer, I found references to this ecu from a posting in 2004:

http://bbs.scoobynet.com/private-sale-car-parts-ac...

Looks like it's the original '95 ecu, I think.

It might have a scoobyecu chip inside the case if its the 95, which is not the best way to control a 2005 2.5, you might be better off getting hold of either an aftermarket ecu, or a 2005 ecu and Ecuteking it

[hewlett]

Hmmm, I think I need to show this to someone, Greenwood Racing are about 5 miles from me so hopefully they can diagnose what it needs by looking at the ecu. thanks for all the help Vixpy especially. Cheers

[Vixpy1]

hewlett said:

Hmmm, I think I need to show this to someone, Greenwood Racing are about 5 miles from me so hopefully they can diagnose what it needs by looking at the ecu. thanks for all the help Vixpy especially. Cheers

Yes, pop it down to James.. , He will sort you out