Depnds on how much the iggy is retarded. 5-6 degrees will make a big difference. And folks, DON'T trust yer timing lights....the harmonic balancers(nor the timing lights) are not always 100% accurate, even when new. Best way to set timing is with a vacuum gauge connected to full manifold vacuum. You want the highest vac reading you can get. Ben(cthulhu) can elaborate more on it, but ever since he originally posted his method of setting timing using vacuum years ago, that's the only way I've done it. Once I get the thing set right like that, THEN I connect a timing light just to see where it is on the marks, and then I can use that as a starting point from then on.
Retard the timing on yours, and then run the engine at high/fast idle for a few minutes....see if the exhaust pipes at the manifold don't turn cherry red....
HERE'S one of Ben's threads on timing lights, and they're uselessness.....and info on how he uses vacuum to set the timing.
|UPDATED|5/19/2014 9:03:54 AM (AZT)|/UPDATED|
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