I recently put a 1974-76 skylark 350 HEI in my buick 455. With points and my ta cam It ran super at 10 degree's. Now Since the hei and the curve kit was added I used one heavy and one medium spring. I have it set at 13 degree's and at 24-2500 rpm it gets 32-33 full advance. I think it's setup proper but what i'm trying to do is find that key timing mark. So if I could find out the stock ignition timing of a HEI 455 from 1974-76 I can add that to the stock of mine with the points then add the advance of 4 degree's to accomidate for my cam and find the magic number without burning alot of gas and rubber to test the results. Thanks.
