[BarryGMC]

Run the Rochester. Set the carb up for a mid 60's Chevy. Don't be fooled by the Holley 500. Compared to a worn out stromberg the Holley seems great but apples to apples the Holley is crap. The best mileage I have got is with a new ww stromberg. The Rochester should be like the ww in performance on the v6. I run the old Rochester carbs on Chevys and really they are easy to deal with. This group thinks the Holley will give better mileage and drivability but after running 20 or more v6 gmc trucks with every thing including gm tbi the Holley has proven to have the worst mpg. The ww stromberg in new condition has given me an average of 14 mpg in a 3/4 ton truck with 3.54 gears and man trans and 15 in a half ton with 3.07. The best is a tbi in a 1/2 ton with man trans and 3.07 at about16 mpg. The Holley 500 has never given better than 12 mpg. Period... Same truck with the tbi. 66 half ton with 3.07 rear. The Holley really does no good until about 3,500 rpm. Since I really won't run a 305 v6 past 3500 I don't see the reason. Finally I have run the Holley or it's motocraft counterpart on a number of amc v8 rigs and can say I like it on a 304 but that engine runs all day past 3500. Barry