74M35A2
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16 degrees is what the majority of all the 8.3L RV guys run that seek mileage and power gains. They were the largest group of personally owned 8.3's I could find, that tinker with them. Our stock timing is 8 degrees, theirs is 12'ish, and they were noting gains of 2-3mpg by moving to 16, and said any performance mods too much better hold like that. 16 was regarded as the max safe do-not-exceed number for stock head bolts/gasket with no issues. Decreases smoke, decreases EGT. Not really a power gain by itself, but once you add more pump fuel, the results will be further ahead. Should be an instant mileage gain though.
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