Just spent the bucks on a nice timing light and got a handle on the timing. The intial is 15 degrees (too much?) and the final is 30 degrees. I have had backfire problems along with bogging. The question is does anyone have directions on how to get more mechanical advance out of an HEI distributor so I can set up the intial timing correctly?
Big Jim W. setup my 430 with 22* initial, 34* total. Advance your timing 4* more. Don't get so hung up on initial advance. The TOTAL is the important end of the equasion. 15* is fine. If you can run 19* without pinging, it is no problem either (unless hard starts become an issue). At that rate of advance though, you might get light throttle pinging, due to your vacuum advance. The factory ran about 44* total timing at cruise, including the vacuum advance. With 34* total mechanical, you'll only want 10* of vacuum advance, and this is where the adjustable vacuum advance works out nicely. You can turn it down so you only add 10* or so of vacuum advance. This is what Jim set me up at and it runs like a raped ape! You want all your advance in by 2500 RPM or earlier. NO LATER. Good Luck.
HEI Timing sailbrd-I have the same problem as you do. I put up post earlier and asked the same questions and got no answers. You can't set 34 total and take what you get initial because it bucks the starter so bad it won't start. I see where MSD has a box that works with HEI's that allows you to dial in what you want up to 15*. That would probably work but you have to do it manually. I think the distributor needs to be recurved to give you what you want but no one around here can do a HEI??. I think you leave too much on the table if you can't get to 34 total. HELP!!! Mike D.
you guys need to get a weight and spring set for a GM HEI. i got mine from PAW, about 6 bucks. the weights are shaped a little different and will allow more advance, and the springs will help you dial it in to rpm. mine works fine, i can get at least 36 degrees total by 2500, havent tried for more but im sure it is there. i run mine around 34 total usually for street driving on pump gas and have no trouble with it bucking on the starter. current CR is 9:2 to 1, worked jsut as wsell when it was 10.3 to 1.
