best racing ign system.

Speaking of vac advance in circle track, in the 80,s when I ran open motors I ran a vac can dist. I had a mighty vac pump laying next to my seat, if it was tacky, 2 pumps gave me 36 degrees, if the track dryed out I released the vacuum to take roughly 10 degrees of timing out of it to make it lazy, really worked good and no one ever knew.