[Eaglestang]

i noticed there are another kind of throttle body, i looked up at part store , there's edelbrock throttle body, , any difference to engine power or nothing much? even try to swap bigger throttle body? no idea those sizes 65mm? 70mm? or 75mm???

93 mustang h/b
mods:
swapped c3 3 speed transmission (stock is A4LD)
removed cataylist converter, installed straight exhaust tubing 2"
removed silencer, installed 3 inch inner/outer exhaust pipe on intake

[93mustang]

65 will be an improvement on a stock motor with stock intake.
70 with an aftermarket intake like say edelbrock performer specs a 70.
75 is too large, will do nothing but give you poor low end driving unless your running high hp motor or boost.
go with 65 for stock motor.