When I finally got all the kinks worked out on my SBC build:
86-95 350ci, one piece rear, roller cam block, 4 bolt mains, bored .040" over
Vortec 906 heads
LT4 Hot Cam, Proform 1.6 roller rockers, Comp 26918 beehive springs
Professional Products Crosswind (Dual plane, Air gap)\
Balanced ZZ4 rotating assembly, H345NCP-40 pistons, 10.3-1 compression
34 degrees max timing all in by 3200rpm, 91 pump gas
This was in front of a PCM controlled 4L60E with a 3200rpm lockup converter and 4.10-1 rear gears with 30.4" tall wheels on a 4,380lb pickup
Around town I only got 12-14mpg, but on a few road trips from Prescott Az to Phoenix, I got 23-25mpg on the way down the hill and 16-18mpg up the hill.
Since than a few things have changed and I'm not pulling nearly that kind of fuel economy, but I didn't build it to save on gas
Last edited by 04SilveradoMykk; 10-12-2009 at 08:01 PM.