Re: Test Prop Part No.'s.
The test prop for the 60hp is 382861. That number probably was superceded in later years, but the prop measures 2" wide, 10" diameter. Same one is used by the 85/90/100hp V4s, because they have a lower gearbox ratio than the triples. The 50hp twin prop (384769) is 9 7/8 by 2, note they have an even higher gearbox ratio than the triples. The 115/125/135 test prop is 11 1/4 x 2 3/16, except the 135 has a slightly SMALLER 2 1/8 prop. <br /><br />The specs for the triples are 55hp 4600 rpm, 60hp 4800, 65hp 5200, 85/90/100 all 4800 (again different 2:1 gears versus the triples 2.41/1?), 115/125/135 all 4800, 50hp 5300 (2.66:1 gear). They list a different wheel for the 70/75hp triples 5000 and 5200 rpm respectively against a 11 3/8 by 1 53/64 wheel.<br /><br />Note the same rpms across the different V4 hps, but the strong difference in the 50 cubic inch triples. I'm assuming OMC raised the ports on these after they picked up a few years experience.
