i have a 1985 Chevy C10 with a 305 and 3spd auto with 3.08 gears and i have troubles with getting 12 but don't do just to much highway but i should be getting a little better cause the best i've ever gotten was 14 its stock 305 with headers and factory Q-jet 4 barrel and true dual exhaust (2 1/2" pipe cherry bomb glass packs) i'm guessing smaller pipe would help? any ideas
Nate
