Schonye,
The 163 intake vs the lower model in 70 is a no brainer. I dropped an LS6 in a 69 Camaro, made a few passes with it and was unhappy with what seemed like a momentary hesitation standing on the throttle. I swapped out the intake to a 163 using the same carb, made some passes and gained a minimum of 3 tenths of a second on each run, everything exactly the same except the intake. The additional height of the 163 is just enough to allow the fuel molecules to mix with the air causing a less liquid mixture for faster and more efficent combustion. I would think GM only dropped the intake in an effort to engineer the cold air induction system to work correctly with hood clearance. Whatever the reason, the proof is in the results, I definetly gained a quicker ET with no other changes except the intake.
Motown
