i got a 79 corvette and ive been reading that to get the best performance out of the ignition 36 degrees at 2500rpm is the best. has anyone done this in there hei ignition system. if so how do you go about doing this. i do have a timing light so i know that will help
thanks rj

Does your timing light have a dial back feature ?

geo

I am not sure what your setup is like but to set the timing for 36*@2500rpm's you need a dial timing light.
1.) Disconnect and plug the vacuum hose from the distributor
2.) Check the timing at idle for reference.
3.) Have someone slowly rev the motor until you don't see any movement on the timing mark. This will tell you how much movement there is in your mechanical advance and what rpm it tops out at.
4.) Do the math and you will know where to set it at idle. Run the rpm's up again the same way to double check your settings. Reattach the vacuum line.

This may cause the motor to start to ping. If it does, try running without the vacuum line attached or back the timing down a little at a time until it stops.

this is not by the books but how i have my timing set. i advance my timing until either the engine pings or it is hard to start then i back the timing down until both problem go away. I haven't checked the timing with a light but it is running much stronger now. i have used this method for over 25 years without any problem

You need to change the weights, springs, and vacuum advance can to do this properly. A guy named Lars that hangs out on http://www.corvetteforum.com puts kits together. Most of the kits that you can buy only include springs, but the stock weights are shaped such that they don't give enough advance, no matter what springs you put on them. He makes kits to match your engine setup.

I sent Lars my distributor and had him check it out and install his kit. Great job. I would recommend him for the job.