Timing problem when engine warms up??
 

hey i have an 81 Camaro it originally came with a 305 but the guy that i bought it from put an older 350 into the car so its not an actual camaro engine.
The car starts up, idles and runs great until it seems like when it warms up to a certain temperature you can hear it jump out of the correct timing. After this the engine runs really rough and spits and spatters when you try and accelerate and also runs really hot. Could this be an issue with my distributor being worn out? its a mechanical advance distributor no vacuum advance at all. Any help would be much appreciated!!

Do you know what was kept stock, and what if anything was ripped out?
1981 had a computer to manage the engine (oxy sensor, distributor timing, and carburetor metering). If the computer and/or sensors were bypassed, but the original components were still used, they will mess up and not work correctly.

Ok cause i just recently put a cam, intake and carb on it and thats when it started to run like that. And my distributor has another set of wires plugged into it so that would be to the computer i guess.? Theres no way to bypass the computer is there cause that delivers the spark and fuel? So should i just make sure all the inputs are plugged in and working??

Yes the extra distributor wires connect to the computer (ECM). There is no centrifugal advance in the distributor as in old type distributors, the ECM controls timing. And I'm pretty darn sure removing the computerized carb shouldn't affect the ECM timing the distributor. The ECM meters the fuel at the carb based on oxy sensor readings. I presume you put on a conventional, non-computerized carb? But it sure sounds like the distributor isn't advancing. That could explain why it's running like a dog, and running too hot. Connect your timing light, and check where the timing is at idle. Then slowly rev the engine and see if you can watch the notch on the harmonic dampener advance way off the mark. Btw, is your base timing set correctly? What else did you do to the engine, you didn't put in a gear drive timing set? Make sure all wires are connected too. Are you getting a check engine light?

The carb is a holley 650 and im pretty sure there are a set of wires connected to it but that would just be for the electric choke right? Im certain that the timing is set correctly and it starts up good and runs great, so im pretty sure the timing advances correctly but then it seems like when the temp. guage reaches about 170-180 you can notice like a bump in the RPM's like the timing gets thrown off and then it starts running crappy. Could it be some sensors maybe or something that arent connected?? Also i didnt do anything to the timing its the original gear just a new chain that came with the cam

Yes the wires to the carb would be for the choke. Did you check to make sure the choke is opening all the way after the engine heats up? Does it start to run crappy at idle too?

After it warms up it idles at a lower RPM about 100-200 RPM less. If your sitting at idle when it hits that temp. you can hear the engine rev down still idles smooth but when you accelerate it runs crappy like the timing isnt advancing at all.

So you still didn't look with the air cleaner off to see if the choke is opening completely?

Havent checked it yet as i am out of town for work but ill check this sunday and get back to you for sure. Thanks for the help.

Sure sounds like that could be the problem,just like an old q-jet with a bad choke pull off.