357LT1

Ok guys here it is! A little over a year I had my 357 LT1 built with the items listed below. When this motor was fresh I had a hard time putting the power down! I had two good runs that showed me I had a pretty good car, one with a Mecham built LS1 T/A w/ heads/cam and he got me twice and I got him once in close runs. The next was some runs with a 94/95 5.0 and it had heads/cam and 6psi, he said he had around 475hp at the crank? We were dead even on both runs from a row! I ran it at the track once on street tires and ran a 13.6 @110 while roasting the tires on 1st thru 3rd! I never had it dynoed but I knew it was strong!

A few months ago I bought some BFG DR's and I broke my posi within an hour of use! That's when I new my car had good power! I installed 3.73's and I thought it will hit even harder but it wasn't there. I dynoed the car and I was not happy with it! It gave me 321rwhp and 328rwtq! I ran it at the track w/ DR's and I got a better ET but slower trap, 13.2 @105! Car does not feel the same! This combo should be running better, right? What should I see?

I think my Opti is going! What power lose can I see with a bad Opti! Is there anything else I can check? Thank's for the help in advance!

Ramiro

revtime

An opti that is going should exhibit some tell tale signs, is it stumbling or hesitating? Problems starting or does the car die for no reason?
When my cap and rotor went bad I had a low rpm stumbling problem at first that turned into a backfire under acceleration problem.
I changed out the opti and it made a huge difference in how the car ran.
What I am saying is don,t blame the opti right off the bat, I changed some other parts and checked alot of other things before I went after the opti.

357LT1

I do have some issues that can be symptoms, lots of cranking before it starts, backfiring, black smoke on hard shifts, some stumbling, stays at high idle when stoppin before dropping to normal idle, and this tremble in the car that is more noticable around 2500K RPM! I don't know what else it can be unless it's something else in my ignition system!

Ramiro

madhatter

yeah I have had the same problems man.

did that fuel pump help out alot after? I know we test drove it right after, but i wanted to knwo if you have had any problems.

revtime

It sure sounds like an opti.
I would check your coil and ICM and make sure your wire connections are good, you know the basics.
Opti is an expensive and hard to change part, it aint that bad but its not easy either.
So make sure you don,t have any other probs first, I would hate to see ya go after the opti and that not solve your problem, but it sure sounds like it to me.
Any SES light?
Was the opti changed when you did the motor?
My optical portion was still good, no SES, but my cap and rotor were beyond fried.
So if its still the stock opti maybe it needs a cap and rotor bad.

357LT1

Yes, that fuel pump helped some! I gained 15 rwhp and 17rwtq with more fuel! I just know there's something else wrong with the car! I'm going to see if there's someone from AZFBA that can scan my car to see if they find anything. Do you know of someone Madhatter?

Ramiro

Chris 96 WS6

I would ditch those Edelbrock headers and step up to at least a 1& 3/4th" primary shortie header if not full longtubes.

madhatter

Mike Bambic can do that for you. I am pretty sure he has a scanner on his laptop. Matt Diamond also has a scanner, but it is just a generic one that doesn't give alot of info.

357LT1

Thanks Madhatter, I will get in contact with Mike and see if he is busy this week.

Ramiro

5.0THIS

Our cars with stock power can ruin a posi in short notice on BFG DRs, so I wouldnt use your rear axle parts breaking as an indicator of increased power

357LT1

I agree, they can break them!