1badd7

First of all, I read with this setup I can get around 420-440rwhp. Finally got the car on the dyno and first run only showed 270rwhp? We try almost everything we can think of, first we thought the exhaust (because I put a Y after the headers), so we just ran it straight off the headers. NOTHING. Then, we thought the throttle cable wasn't opening the throttle body up all the way. LOOKS GOOD. We also thought the timing chain was installed wrong and maybe a tooth was off. INSTALLED CORRECTLY. Then, we checked if all cylinders are firing. LOOKS GOOD. After all the tuning, we ended up with 330rwhp.
Okay, here is what we might think the problem is. First , we think it could be the head gasket and push rod length? The AFR heads are not milled and we thought the gasket could be too thin/think and push rods are to short/long. Second, we read somewhere that if the alternator isn't charging the battery enough that the spark plugs aren't getting enough spark. We had trouble with wiring up the alternator and had never got it checked out at a shop. So, we hooked up a charger to the car last week and it revved up quicker to redline without driving it, but have not got it checked out yet. I haven't checked the compression yet either.
Car drives great without any hesitation. The two guys that tuned my car also said the car doesn't feel like it takes off quick enough when you WOT. They both have LS1 corvettes. Any ideas would help me out!!! Here is a list of my mods.

2002 LS1 FIREBIRD
SPEC STAGE 3 CLUTCH
JTR 1 3/4" HEADERS
AFR 205 HEADS W/66CC(not milled)
COMETIC HEAD GASKETS (.O45)
COMP CAM PUSHRODS 7.4
COMP CAM 54-444-11 224/230 (intake .581)(.588 exhaust)(114 lobe)
42LB INJECTORS (AEROMOTIVE A-1000 PUMP)
NGK V-POWER TR55/ STOCK # 3951
HP TUNER PROGRAM

Thanks guys, James

Grimes

iTrader: (3)

I would start with some simple things first. How is the AFR on the dyno, are you sure you are getting enough fuel pressure?

slow trap

iTrader: (22)

what intake are you using ? through a 90/90 you should be in the area you was hoping for.around 425 rwhp,400 rwtq.even with an ls6 you should have been close.i didn't look but was that on a dynojet or mustang ?

Ragtop 99

iTrader: (7)

Doing a compression test wll answer some questions and give you a chance to look at the plugs.

Are your o2 sensors working right?

Mustang dyno or dyno jet? Its low for either but the magnitude of the problem changes.

OJmobileII

iTrader: (3)

wouldnt make up the difference between 330 and 430 that ur looking for, but did u degree the cam? check the compression. is this an a4 car? how accurate is this dyno, have previous cars' numbers been down? correction factor? so so many factors... i would do basic checks and maintenance on the car and if everything checks out, i would not worry too much about the dyno.

1badd7

Thanks for the reply!
We are getting enough fuel pressure. It does have the 02 LS1 intake manifold. o2 sensors I think is working fine. A/F ratio looks great on the dyno. Any more ideas would be great. Thanks

slow trap

iTrader: (22)

mustang or dynojet ? also if the manifold is off of an 02 it is probably an ls6 manifold.

slick1851

Go through everything! Do a compression test on the motor also

1badd7

Forgot to mention, it was on a mustang dyno. James

AdamSS

iTrader: (3)

It's way too low, even on a mustang dyno...

Can you post up a dyno graph ? I'll bet the cam is not degreed, and your timing is off.

My friend's friend has an RX7 with Ls1 engine in it. They installed a Patriot Stage III heads and cam package. Got 430 rwhp on that combo...

Who installed your engine ?

1badd7

I didn't get the dyno graph, too pissed off and forgot to ask for one. I'll try to get one soon. My brother and I installed the whole swap. James