When gas was $4 I decided I was going to make some mileage improvements with my 37 Buick with the old straight eight engine with 16mpg being the goal (never got there). First I put it up on the chassis dyno and dialed in the best possible settings. I have an Oldsmobile V8 HEI distributor in the straight 8 which I matched the distributor curve and rate of the Buick distributor which proved to be wrong and was corrected to give a better reading. The guys at GM hit a home run with the Stromberg 2bbl and trying others gained nothing. Going from a 180 T-stat to a 195 gained a tiny bit as did an electric fan but I've gone back on both. Switched to the high dollar Torqo synthetic fluids and lubricants in engine/trans/differential and after chasing all the leaks down did gain about 1mpg. The biggest gains came from removing the sun visor, outside mirrors, Breezies, and anything that caught air. The 8.25/15 bias ply tires to 2.25/75/15 radials inflated to 38psi resulted in the largest gain---a bit over 2mpg. As Jerry advised; you have to make several trips spread out over at least a couple months time to really show whether your efforts worked. Mine took the old girl from a 12mpg glutton at pump to a not so embarrassing 15.8 at 70mph highway steady cruising. I think peoples belief that there is magic in camshafts and carburetors often hides the woods behind the trees.
