Went back to the dyno today. I had gutted the cat :rolleyes: in an attempt to see if it would let me pick up a few horses.

I did pick up a few HP from 2000rpm-3700rpm, so my butt dyno wasn't lying to me completely as you can see here(this is my best run from last month, and my first run from today):

http://s92247691.onlinehome.us/avenir/comparison.JPG

Then I bumped up the timing. It was hard for me to see *exactly* where it was at because of the lopey idle, but its a LOT closer to 15 than it was before which was probably below 10*. The timing netted me another 10hp, and another 15lb/ft.

http://s92247691.onlinehome.us/avenir/newdyno.JPG

So, not horrible, I found a few horsies and the power curve is a tiny bit better and I need to richen up the a/f a tiny bit and fix that little dip at the end, but otherwise I'm done with power stuff for now. I bet cam gears would add a few horsies when tuned properly.

very good :biggthump

Good numbers, do you have cams? I would recommend some s4's and gain a good 20hp.

aren't s3's better with turbo?

What are your mods?

aren't s3's better with turbo?


nope ;)

I could lay my dyno over that, I swear it would be exactly the same.

Travis E.

nope ;)


:o explain...because i believe it was you that told me a few months ago that S3's were the best cams you could get for a turbo setup...

What was the boost level? I think you still have alot more power to put out.

Regardless that is still some nice whp to be rolling around with.

S4's are better. Period. I don't know why JWT would make S4 (4 being greater than 3) if the S3's were better? Now the S5's are out and everyone wants those. The S4 has longer duration I believe, making them better, and they get better with cam gears to dial out the overlap.

That's the reason I was hoping for more. I already have the S3's in there. The boost is at 10psi. It has full boost at 2850rpms according to the VDO boost gauge and the SAFC.

The setup is: Avenir DET, some OEM FMIC I got from the motor importer, JWT S3 cams, VRS 2.5" mandrel DP, 3" crush bent exhaust, gutted cat, 2" intake piping from the turbo to the TB, SAFC2, 370cc injectors at 4bar with Nismo FPR.

Well, those are kind of low numbers, why are you running 4bar of fuel pressure though? 38psi on my high compression SR was still way too rich in the 10:1 a/f ratios. Also, I would say the cat is killing you. Even with it gutted, you are still losing power. Pay $50 and get a test pipe, and I say 5-10hp. Also a 3" DP wouldn't hurt either. Remember you have low compression so you aren't going to get the same numbers some of the DE(T) guys get. I had 219/238 with a 2" exhaust stock cat on the USDM motor.

I'd say a little low too, as I made that power without cams. That dip in the A/F is killing some power up top. I have a 3"DP and 3" Cat and exhaust, IC piping is 2 1/4. JWT(gasp) ECU 370s 4-bar. here's mine to compare. A/F are not right.

http://www.sr20forum.com/img/data/500/308AVdyno.jpg

Travis E.

Well, those are kind of low numbers, why are you running 4bar of fuel pressure though? 38psi on my high compression SR was still way too rich in the 10:1 a/f ratios. Also, I would say the cat is killing you. Even with it gutted, you are still losing power. Pay $50 and get a test pipe, and I say 5-10hp. Also a 3" DP wouldn't hurt either. Remember you have low compression so you aren't going to get the same numbers some of the DE(T) guys get. I had 219/238 with a 2" exhaust stock cat on the USDM motor.

I'm running 4bar because a few of the guys on here almost flipped a sh*t when I mentioned running 10psi with a T25. That, and I figured it can't hurt if I upgrade other things in the future.

Could you explain why a gutted cat would be killing me? Its completely straight through, I don't see much difference physically from a test pipe....

I didn't go with a 3" downpipe because the roads around here suck terribly, and the 2.5" one scrapes a bit already.

turbulents

Get rid of the gutted cat. Its hurting more than helping. That is a low dyno number for 10psi and S3's.....

The cat is hurting you because its making the air go all around that open hole rather than straight through, like a straight pipe. Picture the air encompassing that big oval and then being forced back into a smaller passage. Like muleman said, turbulance.

Ok, that makes sense. Unfortunately, that doesn't really matter to me at the moment because CLUTCH SPECIALTIES CLUTCHES SUCK! This one only last 2000 miles. I have a feeling it spit another spring. Same symptoms as before, clutch pedal up or down, it will not go into gear. :(

Anyone feel like lending a forum member a helping hand with the ailing car?? I'm so upset right now...

Go with a 3in dp and no cat and tweak the afc some more. Fix that dip in your a/f and give it another go. They're just numbers man don't be stuck on them so much.

Thanks Peter, I'm not really concerned with the numbers. The car feels great now. When its running.