[olddog]

Thanks for sharing. There was a lot of good information in there.

I am hoping someone can answer some questions that were not talked about. With centrifugal advance most people say it should start just above idle, around 1000 rpm and that it should be fully in by 3000 rpm give or take 500, depending on who you talk to and what engine it is. What I have never heard discussed is should the advance be linear with rpm through that range or is it a curve?

Say you want intitial at 12^, and the advance to start at 1000 rpm, and at 3000 rpm you want to add 24^ to the 12^ for a rotal of 36^. If it were linear the advance would add 6^ at 1500 rpm, 12^ at 2000 rpm, 18^ at 2500 rpm, and finally the 24^ at 3000 rpm.

Intuitively I would think it should be linear. But intuitively it seems to me that an engine turning 10K rpm would need more advance than one turning 3K.

Anyone ever map this out and see. I would, but everything I own is EFI.