Well I just got my camaro running again w/a Rochester Qjet. Something was wrong w/the Holley, my brother's working on it. Old spark plugs were completely black. Changed those, put my bros Qjet on. Now the car runs fine but its been dieseling everytime I turn it off. I changed the timing and the idle, could it be something w/the carb? The dieseling only lasts about 2 seconds. I really want to get that 383 on the road again.

 

Sounds like its getting too hot, or the idle is too high. How high is your idle speed? if its over 1000, its probably too high.

If not, then it may be running lean.

 

My car used to diesel bad. If the idle was like 1k it would diesel. I turned the timing way down...ran 93 octane...nothing fixed it.

Finally I installed a lt4 camshaft and waaallllaaaa no more dieseling...even with more timing and a higher idle...

I suspect a leaky intake gasket. Only thing I can figure.

 

What dist. are you running? Hei advance wieghts can stick. Try cleaning and a little lubrication on the posts underneath them. You might have too light a level of springs on them or one has come off the spring mount. Any way make sure they move freely in and out. Just a thought, It's happend to me before. High carbon deposits on the valves can cause this problem also.

 

Running really rich will cause carbon deposits. What happens is the carbon get so hot that it will ignite the fuel even after the ignitoin of off.

Make sure the timing is no more than 12 degrees or so at idle, and try running some 93 octane and some octane booster to help clean everything.