Per:
AMA (U.S.) 428 rules only allow unmodified wood props with a min dia of 8.5" or APC racing props (D-1 hub) of 8.75" min dia. These props work pretty well as the current U.S. record is 1:03.9? on our long course which is about the same length as the F3D course but configured a little differently. We also race APRA, like 424, out here and the only prop permitted is APC 9x6.


Barry