LT1 Camaro Timing Issues

[camaro95]

Thanks Pete but dowel pin on cam is good.

[Lee Valentine]

If the rotor mount was not tig welded to the distributor shaft it probably spun and is out of phase. hope this helps. replace dist. with another and see if it runs

[Ed Wright]

If you are using a crank trigger, the Opti has nothing to do with your ignition timing. Only injector timing. Usually when they do that on a pass, the blade on the rotor was hit and knocked to one side. You would have seen that when you had the cap off.
An MSD rotor won't do that. There is a fix to prevent a factory rotor from doing that.
So, you have even had the timing cover and c sprocket off?
Guess your crank trigger stuff was still tight?
Your dampener is keyed to the crank? The LT1s are not from the factory. They can slip on the crank. That would do it.
If you haven't already, I would check my cranking compression.

[Rich Biebel]

Line up your crank trigger wheel and timing pointer on number one cylinder.......pull the cap off and see where the rotor is pointing to in the cap.....if something happened to the distributer or cam you should see it there...Rotor should be pointing somewhere close to number one terminal in the cap. I would bet it is not....and something failed like Lee pointed to.....

Do you send the crank trigger signal into your ECU and then to your ignition box......or bypass the ECU and direct to the ignition box with locked timing....?

I ran my LT-1 with locked timing and did not use the ECU to change the timing.....

[camaro95]

Thanks everyone for the info. Found rotor hub had slipped causing #2 cylinder to fire when #1 was suppose to. Not sure what caused it to slip, no damage to the rotor or cap was seen. Runs good now, hopefully no damage from the backfiring at high rpm

[Ed Wright]

Cheaper and easier than having keyways cut, you can do like many have done to LT1s with blowers. Drill in from the front, between the crank & hub for a 1/4" roll pin. Drive that thing in there, it will be half in the crank snout & half in the hub.
If this is a Stocker or Super Stocker you should be running a SFI dampener anyway, which will already have a keyway. The crank should already have one. Put the key in and nothing will slip. I would recommend an ATI dampener.

[joelster]

Glad you found the problem!

Side note for you guys especially PETE- how many times have you seen LT1 cars break the dowel pin off?