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Old 08-29-2012, 09:04 AM
oldchevy1956 oldchevy1956 is offline
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Well, I spent a good part of Saturday morning dialing in the timing. All seems to be real good now with the idle and drivability. I can go through stop and go traffic, cruse at highway speed, and have awesome WOT. I can even do a decent burnout which I could never seem to do before. I am very pleased with my adjustments. Thanks to all for the advice and help. So here is what I did...adjusted the distributor to ensure/adjust it for the mechanical advance curve and max advance, and yes I am still using the Mallory dual point distributor which is working very well now by the way with my old school technology. I did not mess with the carb as I plan to replace now. But for base timing we are at 24 degrees at 850rpm. You can now really hear the cam. When I put in gear the rpms drop slightly but no engine issues with missing or sputtering like it did before. I also changed the vacuum advance to be ported so no vacuum advance at idle. With vacuum advance unplugged, my mechanical moves the advance to 35 degrees at around 3000 rpm. When I plug in the vacuum advance the total advance will move to 47 degrees. The engine really seems to like these advance settings. When I move the base back to 20 degrees the engine will loose power at acceleration and probably at WOT, and when I move to greater that 26 degrees of base timing I begin to get detonation, so hence I have it set to 24 degrees.

Now I am really thinking of leaving the distributor alone at this point even though I am getting many suggestions to upgrade to an electronic distributor… which I most likely will upgrade in the future, but for now I am going to invest in a bigger carb. I am sure I will have to dial in the carb as well but I don’t want to change both carb and distributor at the same time. Again thanks for all the advice as, even though I have been setting timing and such for a long time on cars, I was struggling with this particular engine for some reason.
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