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View Full Version : wheres the power going? subaru mechanics we need your imput!



SPR
08-08-2007, 12:13 PM
okay guys i need to rack some brains. we just found a problem in a friends wrx. so help me out here. and i know this is a legacy forum, but look out for your fellow honda smokin subys and help us out here.

my friends 06 wrx with a DP and exhaust runs pretty close with my 06 sti, i can pull a ave of 13.3's and him 13.7's now our other friends 04 wrx full on stage 2 (cat less up pipe down pipe full invidia turbo back exhaust intake and PDX tuning did a ECU reflash. suppose to be around 250 hp to the wheels. this should keep up easily if not pass the sti and the 06 wrx with out question. they are both running less than 230 whp. but it just feels gutless, you jump in the sti or the 06 rex and they snap your neck with power, pick up fast threw the gears and flat go. the 04 slow threw the gears doesnt snap your head back that hard, just doesnt seem to have the power it should. now even though its a 2.0 motor, and not the 2.5 like both the 06's it shouldnt matter, it still should be tuned for 250 whp. there is no obvious signs of a bad tranny or clutch or something, but does anyone have any ideas where the power is going? and what to look for? it obviously in the drivetrain some where. but we want a idea on what to look for before we tear into it, or worse have to take it to the dealer. give us some thoughts!!! thanks

and its not a loss of boost judging by the boost gauge, its peggin 15-16 psi at peak which is a lot more than stock, and still more than a stock sti.

not sure if this will help but he had been running DP, exhaust, and intake. and we ran a 05 RSX with exhaust (high 14 second car). from a 20 - 70 mph roll the wrx beat him but not by much. but from a 60-100 the rsx walked all over him. then he took it to pdx tuning and had the catless uppipe and the reflash done and we cant really tell any difference at all in the power, although we havnt raced it yet to see. unfortunatley its never hit the track yet either so we dont have any numbers on it.

and you can rule out driver error. all 3 of us have drove it, and tested it, and it really is the car. it doesnt take a genious to put the peddle to the floor and tell it doesnt pick up as fast as the 06, shifting or not.

any ideas?

MCarp22
08-08-2007, 12:37 PM
Does he have a dyno chart? Or are we relying on what someone who "tuned" it is saying?

SPR
08-08-2007, 12:44 PM
we dont have time to get to a dyno yet, but pdx tuning is one of the best subaru tuners around. very knowledgeable and they have done a ton of subys. they know what they are talking about, i trust that their guess is somewhat close since they are talking from experience. the ecu was tuned with a stage 2 map which was designed for his exact mods. car should be running strong.

deadlydave
08-08-2007, 01:07 PM
What about the torque figures? Do all the engines, at least in theory, produce the same amount of torque?

SPR
08-08-2007, 01:12 PM
no, the 2.0 does have less torque and a crappier torque curve. but this should be a mid to high 13 second car as is. based on a 02 wrx with the same mods. and my predictions are its a mid 14 second car.

omahasubaru
08-08-2007, 02:04 PM
a small turbo on a larger displacement motor will spool so fast there won't be a 'turbo snap' when power hits.

TD04 on an EJ25 is going to be that way... as was my swapped 2.5 block under a version III STi top end w/ a VF30. I was hitting full boost of 15 psi at ~2800 rpm. No snap when boost kicks in as it is there all the time and early.

EJ20 w/ TD04 will have lag, even if you max out the TD04 like I had on my previous WRX... it still has some snap. STi has snap as it's a larger turbo. Tuning is a big factor as well in the STi for noticing some snap.

I think you're being paranoid... or desiring more lag to just have that 'snap'.


My $0.02

Reason
08-08-2007, 02:18 PM
I would have to say that the 2.0, smaller turbo and it need to be tuned. I don't think a "reflash" will get the job done.

Khanhfucious
08-08-2007, 08:59 PM
Ive seen this thread on so many subaru forums now...