This was my thinking, the car is never really to the floor. Driveability is the program here, I know the thumper cam isn't really the ideal choice here, he had to have the choppy idle. Lol
Oh yeah I gotcha! If it’s a complete and total cruiser, the 600 will be fine. It’ll Have plenty of power to get on the highway when the four barrels open up. Also, excellent throttle response.
The 750, will offer a bit more power under all conditions. But! If you don’t get that carbureted tune just right it will be a little sluggish on the takeoff.
With a Carter Square bore carburetor, I prefer to undersize just a little bit. Even more so when the gears are below 391.