Generally speaking, which 13b would be better for performance street use..a 4 port or a 6 port? My thoughts are to have the engine built from the ground up with lighter rotors, street-ported housings and hardened stationary gears. Unfortunately I can't afford to do everything at once so a blower or turbo will be added in the future. According to my reading, Mazda only used a 4 port desing for turbocharging. Can a 6 port be turbo'd?

Before anyone asks, I'm not interested in a 20B.