on basicaly a stock motor at this time how high can i run the timing on my 82 z? at the stock 10 degress my ran ran low 17's. i advanced the timing to 20 degress now it runs mid 15's. how much higher can i go?
20 is pushing it. I ran about there before and the motor went to heaven. I guess silent detonation. About 17 is going to be max safe range on stock engine. raise the compression and cam, you can push to about 22-25.
If you get better performance at 20 degree BTDC, then it is very possible your distributor is messed up. Either your vaccume or centrifical adavance is not kicking in properly. Put your advance down to 12 and rebuild your distributor.