Ok, I am back, got the Flu /cold in October, better now.
We put the Engine back together with the 4th notch at the Crank which is 8 degrees advanced at the Crank and 4 degrees advanced at the Cam. Normal factory setting is 113.5 and we are at 109 to 109.5. We road tested several times and without running the AC the temp came up and that should not happen. Because the Head was shaved, guess 0.010" we think with the extreme advance and increased compression, we over did it, as far as the Cam advancement is concerned. As some of you said to go back to the factory setting of 113.5 and be happy with that, I tend to agree, this is not a race car and at least I finally degreed in this motor and learned about advancing the Cam. We are pulling the timing cover once again hope fully for the last time. I did notice that the Vehicle takes off the line well with the 109 BTDC advance as the racers like, but in my case, I don't need the extra heat in the motor running on the street, most racers aren't using AC anyway. With the rebuilt Heads I am in new territory, like starting all over learning what this motor now likes to be tuned at. First things first, no more advanced Cam, at this time, going back to 113.5, so I can break in the Trans. Fortunately, the Trans. works well, thank GOD. I am posting the tests that we have performed over the last month or so. We think the Pontiac and 421 mods lowered the temp. but we can't prove that until we pull all the unnecessary advance. We Have the Ign. timing @ 6 degrees BTDC and we are all in by 3000-3500 rpm. We did the compression test both wet and dry and the numbers look fair for the age of this Engine. Thanks for the advice in advance and further testing is needed to see if pulling the advanced timing at the Cam keeps the temp. normal. I believe that rebuilding the Heads changes everything. JMO, Mike out.
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