Timing Trouble

[skibullfrog]

I have an 81 GW w/ 360 TFI, cam, headers, performer, etc. I am at sea level and need to know the proper timing. When I get the throttle response good, its hard to start, when I adjust the timing its starts easier but runs poor. Also I continue to have intermitent ping under acceleration. Everything under the hood is new. Please help, and at a minimum I need the correct timing number. Thanks

[Bob Barry]

Stock, it should be in the 10º-12º range.

You could try tightening up your vacuum advance unit so the advance comes on slower. To do that, stick a 1/8" allen-wrench into the vacuum port on the advance unit; turn it counter-clockwise to tighten it up and slow down the advance, a quarter-turn at a time.

If you still can't achieve the ideal balance, you might try allowing the mechanical advance to kick in a few more degrees on initial takeoff. If you remove your cap, rotor, trigger wheel and magnetic pickup plate, you can access the springs for the centrifugal/mechanical advance. There is a heavy and a light spring. The heavy spring wraps around two tabs, and has a bit of play so that the lighter spring allows a lot of initial advance, until that slack is taken up and the heavy spring is allowed to take over. If you want some more initial advance, you can INCREASE the slack in that heavy spring, so the light spring is able to allow more advance off the line before the heavy spring steps in to slow down the advance curve.

This is a kind of hit-and-miss adjustment, however, and it's a lot of stuff to remove to make adjustments, so that might be a last-ditch resort.