I did an lt1 swap into my car and its been problem riddled but I'm slowly figuring stuff out. My problem is is that when I start the car cold, it starts up almost right away and runs decent, but after the car has run for a little while it after I shut it off and restart it, it gets harder and harder to start an the idle gets kinda bad and it will misfire a little. Also it bogs at idle when you try and give it gas. I pulled the plugs and they all indicate its running a little rich. Could this be a sign of a bad optispark? I replaced the icm already so that's theoretically good. One more thing is managed to over fill my oil by about a quart. So when runing the car it bellows smoke, and there is oil comming through the exhaust. I drained some and it's a little better but still smoking more than normal, so would it still just be burning out the oil in the exhaust or o you guys think I have bad rings?

 

No input?

 

It sounds like you have a lot of things going on, you also haven't filled out your vehicle information so we have no idea what car you have, or what year the LT1 came out of. Not that that info is terribly important, but couldn't hurt.
Do you have any trouble codes?

You need to get your oil level correct and let it run until it burns off any oil in the exhaust before trying to troubleshoot that as an issue. Did you pull this motor yourself out of a running car or did you buy it as a package?

From your symptoms I would not suspect the opti spark, I would lead more towards a bad o2 sensor.

 

Its a 96 lt1 out of an impala. I did drain the excess oil and the smoking got a little better but I only had it running for about 15 minutes so would that be enough time to burn the oil out of the exhaust? Unfortunately I did not pull the motor and I took the guys word that it was a running engine but it has sat for a while im guessing. I put in new o2 sensor so theoretically they're good. maybe

 

Normally when I have a car that had oil or water in the exhaust I take it on a drive and run the RPMs up on it to burn everything out. Depending on how bad it is it only takes a few minutes until it starts to clear up. Your other symptoms may be attributed to oil in the combustion chamber also...

Since it is an OBD2 PCM you should be able to go just about to any garage and have them pull codes or datalog and see how the sensors are reading. I'm leaning towards o2 sensors simply because it seems to be a closed loop symptom. It starts and runs fine when it is cold, is this everytime you leave it parked until the motor cools down, or just the first startup of the day?

Did you just put it in, or did you do a tune up on it before dropping it in?