[mr0077]

Wayne, good writeup! I've been doing this for years, and still found this accurate and interesting.

Old Dog, I don't think Wayne is saying that lighter cars can take more timing...he said FE's work best with 34-36 degrees, so total timing, for power, would not change with the car weight; what he is saying (and I really don't know the answer) is that a given engine in a lighter car can take more timing earlier in the RPM range (under 3000 RPM or so) without causing pinging or detonation, as compared to that same engine in a heavier car, yet still need the same max advance for peak power (5-7K RPM) in either car.

Great thread, and good tip from Tom on bug-sucking.