[Huck]

I have tried 3 different aftermarket aluminum intake manifolds on SBC with a drop in torque and a loss of 2mpg typical. I reverted back to a stock intake (either steel or aluminum) with a converter carb spacer then an edelbrock 1406 carb. That has been the best setup for toque and MPG. I also tried a set of hooker headers and also saw an immediate loss in low end torque and a loss of MPG---went back to stock exhaust and regained the mpg and torque. Trucks like low end torque and are usually geared too low for high rpm benefit. I would opt for 307 or 340-350 gear ratio for best results.