Originally Posted by eric32
Sure Was lg1969. I tried original initial setting with vacuum advance hooked up to full manifold and with ported and it did not make any difference either way and added some extra timing and tried both ways and it still did not work right. It was up at my dad's house over the weekend and he thought it must be close and maybe I tried too much but not enough so he adjusted the initial a hair at a time till he got it just perfect and it only needed just a few more degrees but any more then that and it caused its own problems but he tried with full manifold vacuum and it for some reason was too much so put on timed and walla it works perfect and has real nice throttle response and responds nice and quick. I was only off about 4 degrees give or take. I tried adding more then that and it did not help as it was too much and caused other issues. Hard to believe just a few degrees too much or too little can make that much of a difference but this was a learning lesson for me that's for sure. Thanks guys
Your experience is exactly why I keep preaching that even w/similar combinations there is NO ONE TIMING SETTING that can be given over the 'net that will be perfect in all cases! And yes- just a few degrees one way or the other DOES matter!!
A word on giving exact timing recommendations
It is all but impossible to give exact timing numbers because of the variations in engine builds and conditions in which these engines run. It is always preferred to work up to the optimum timing a step at a time. This is the safest way to go about it. What has to be avoided is too much timing under load; too much timing under load can cause engine-damaging detonation.
But any way you slice it, it's still trial and retrial to get the curve dialed in. No matter what we do (short of digital control), the timing curve is always somewhat of a compromise, being as how all engines and vehicles (and all the other considerations) are different from case to case. So don't be surprised or alarmed if you end up with a curve that is different from what is presented in this article.