Car: 1972 Vega with 2300 (140ci) motor.
My problem is cracked rings - On back roads I test and adjust my ignition timing a little at a time by advancing the timing and about when the motor is really starting to run strong the motor busts a ring(s).
I can't hear any detonation, probably cause of the after market solid lift cam. It's a mild cam, cut to run with stock pistons, headers, HEI distributor and a larger carburetor. I'm running 1-Weber 45 Sidedraft.
I have since purchased a timing light with the built in advance function so I can tell exactly how much total "advance" I'm giving the motor so I'm not busting rings anymore.
But now I wonder if there isn't a "rule of thumb" in regards to ignition timing and cam shaft timing, as in - if the motor runs better with 34 degrees total advance at 3500 rpm's - would "advancing" or "retarding" the cam by means of an "off-set" bushing help me optimize horse power/torque. Not sure how much ignition advance the motor can take, but I feel comfortable that a total 34 degrees is safe - beyond that, I ain't so sure, but the motor would like more.
My thinking is, by using an "off-set" bushing to adjust the cams timing, I'd be able to move my ignition timing around to get the extra horses without "advancing" the ignition timing too far.
I'm probably way off in my thinking on this, but you never know.
I know a lot of the folks on here have plenty of experience putting motors together and tuning them - I'm a big car enthusiast, but I don't have a lot of experience tuning out motors with performance parts in them.
Thanks,
Cliff