Model B Carburator

[Big hammer]

My 31 Tudor with 6.0 head , 330 touring cam , counter weighted crank , larger valves, stock intake and stock Zenith carb , Aries muffler, Mitchell’s OD , 3:78 differential gears ,will do about 70 mph flat out level ground or going down hill with a tail wind , is it aerodynamic’s or the smallish intake that keeps the top speed about 70 mph ? How much faster do you want to go ??? Please don’t tell me that you’re a idiot , only did it a couple of times in controlled conditions !