1974 Super 320 prop?

[holokai]

I have a 1974 Super 320 with 318's does anyone know what props originally came on these boats?

[rjrva]

I have a 1971 with 1-1/2:1 reduction. Original props were 17x17, w/ Chrysler 318s. I replaced them with 17x15 cupped and got much improved performance.

[dunakin 28]

I have a 1973 super 320 with twin 225 I looked at the props they are 16 x 15 three blade. the max rpm i can turn is 3600 the gps reads 28 mph:001_cool: from what i can tell if i can tune engines to turn 4200 I should make 34 mph