swtmerce

Hi. I have a STi V4 that has a decat downpipe and H&S backbox. I recently had it rebuilt and it feels stronger than ever. It's been on the RR before (304 bhp) and that was before she spun her big ends.

I am considering putting on an ECU (e.g. Apexi Power FC) and wondered whether it would actually make much difference? I know that UK turbos can get great gains (circa 220 bhp - 280 bhp) but from what I read it seems older STis like mine don't make such huge leaps. Of course, peak power is only half the story; midrange torque is where it's at! So, I'd like to know of any STi v4 owners specifically who've had an aftermarket ECU that can tell me what difference it made. Thanks

Mad Hammer

iTrader: (55)

You could expect to see something like, 330-340 with the standard turbo and injectors using an Apexi ECU or something similar.

Hol

iTrader: (1)

I had a link ECU with decat and cone filter on my Type R v4.

Running straight pump Optimax and no additives, it was no more powerful than standard ECU'd cars running octane booster with the same mods. (Circa 315bhp). Just cheaper and safer to run all full chat.

for some reason, the ECU Tek'd V5/6 (include P1) cars seemed to run better that their v4 counterparts. Personally, I think this was because the VF24 fitted to the version4 is not as good as the VF28 fitted to the V5 onwards cars.

Before I sold the car, I was considering a TD05FE as the next logical mod to get to mid 350's, with minimal lag.

swtmerce

Yeah, it's the safety aspect which appeals to me I guess. I had to rebuild due to oil pump failure. I don't want to have to rebuild again due to detonation!

What about power curves? Although your peak power didn't really change, I'd hope the curve was taller in the lower rev range

Scoobyslammed

Mine shifts, i'm running Gems... with a few other mods... lol

swtmerce

Yeah, only a few other mods! I know who you are......I've seen your car.....

You have one hell of a nice motor.

scooby-tc

iTrader: (2)

I have an STi 4 type R with lots of mods including Apexi Power FC ecu,FMIC,550 injectors,gruppe s headers,helix up-pipe,td05/06 20G turbo etc list is endless

its going on the rollers next weekend so i will post up results but standard with just apexi fc ecu it made 309 bhp/270 ftlb

swtmerce

TC, at what revs were those peaks produced? My car in completely standard trim except decat downpipe (and before she blew) made 304 bhp but that was right at the end of the rev range i.e. 8000 rpm. Torque was about 250 ftlb at 4750 rpm

scooby-tc

iTrader: (2)

I beleive it was at 7200 rpm i havent got the dyno sheet to hand but it was made at power engineering (i know they are opimistic)

Hol

iTrader: (1)

Thats roughly what mine made with the link/decat. Although I got a bit more afterwards with a bigger intercooler and water injection.

The car WAS great to drive on the road and RR operators often commented that it felt quicker than the results showed. That could be the TypeR gearing, or just the fact that the remap allowed better delivery earlier.

Unfortunately, all my paperwork and printouts went to the new owner 18months ago.


I would save just that little bit extra and go for a TD05 series turbo, bigger injectors/pump and perhaps a frontmount. strategic buyer should get you that lot for about £1100.

TC, has gone to the upper regions of that with his 20g. He should be looking circa 400bhp and 380ibs torque plus.

Scoobyslammed

Cheers... if you shop about... Gems, Motec etc can be had for reasonable money... there is other stuff about though...
Before I went the EJ22t route etc... I was running a VF34 on my 2 litre with the Gems... and to be honest... that went very well... TBH it was more than enough for road use...

swtmerce

Cheers for the advice Hol. I was thinking an initial step which should net me 310/310 could be an ECU with ported OE or aftermarket headers? (Oh, and add a pump for safety) Do people think this is realistic?

swtmerce

Add to my last post - if I add a VF34 (which I believe can be bought quite cheaply secondhand) to the headers and ECU maybe I could see 330/330? And that would be for about £1300 all in?

Hol

iTrader: (1)

The most you would see on the 440 injectors, with increased fuel pressure (Pump and regulator) would be 320.

310bhp would be achievable, but your torque is likely to be around 295.

Personally, I would go for the TD05FE, rather than a VF34. Its cheaper and easier to find.