he already said the timing was tried at 8-12. two dizzy's doing the same thing ????????? not likely.. three carbs all doing the same thing again not likely. as for the vacuum gauge if you have no base line and the car idles fine tell me how your going to read it???? the car pops on heavy accel not sure how a gauge will show anything there...i'm not sure way you would run as much int timing as you can?? i run all may sbc with locked out dizzy's. is there something that i don't know about as to way you wouldn't run 20deg of int???