I'll ask here since there are more LT1 people watching this..
I dropped an LT1 into my former TPI car.. It's runnign lean.. so i stuck a fuel pressure gauge on it..

Idle 35psi
WOT 42psi
turn off 35psi and crept up to 42psi.

does this sound right?

It shouldn't actually creep up after it's shut off. It should slowly decrease over time keeping some pressure in the line to ease the next startup. What makes you say it is running lean?

when i say creep up.. i mean over about 5-10 sec.. and then over a couple hours goes down..

The spark plugs are white.. instead of a nice golden brown..

I'd say the fuel pressure sounds o.k. Did you happen to put in new injectors when you did the swap? If not, how many miles are on them? The reason I asked is the tips if the injectors can become dirty or semi-clogged over time causing the duty cycle per side to rise. You may have other symptoms though, such as longer than normal crank times, hesitation, etc.

when i got the engine it had 90K km on it so i'd say original injectors.. if there was an issue with the injectors you would think that only a couple would be lean and not them all.. I checked all the easy ones since i lent my jack away.. 1-3-5-7 and 4 all the same and all lean (white on plug)

I checked the IAT.. at about 15-18 celcius.. it read 2.75 on the 20K scale... I assume that is 5250ohms.

One thing that can cause a lean condition also is an exhaust leak before the o2's. Is your PCM running a stock program and have you checked codes?

an exhaust leak is possible.. don't believe i have any codes. the only thing i changed in the pcm is the fan turn on temp.. the max speed and turned off the egr, vats, braking crap.. didn't change any of the "meat".. im using tunercat though..

is there an easy way to find an exhaust leak?

that program in the pcm is for an auto.. i have a t5 behind it.. does that make any difference? i assume that wouldn't have anything to do with the lean.. but does it make a difference?

Start the engine on a cool morning and you can see it.

Exhaust leak....depends on where it is leaking from.

You shouldn't have any problems running the auto program with your T5 other than a service engine soon light indicating trans problems. I may be able to get you the program from my PCM. It is a slightly modded T56 program. I just have to figure out who has my ALDL cable

if all works good for u.. that would be great. im planning on getting a t56 soon anyway.

dude......transam#5 that thing in your sig that tells you about your computer specs. Thats kinda freaky. how does that work?

Like Trans Am said, you won't have any problem except for SES codes and the idle is set a little lower than what it is for a manual car. Also, if you want the car to idle right when you're driving it and not stall when you come up to intersections, MAKE SURE you have the VSS connected properly. It plays a big role in the IAC control.

Also, if you have the ALDL cable, I have a stock T-56 program I can send you.

well if you have a stock program for a standard.. I wouldn't mind a copy. blackgta@hotmail.com

I did get the VSS hooked up .. but never experienced the stalling at the intersection b4 it was hooked up.. I just figured things would run better with it hooked up..


thanks.