2005 Merc 40m mods for river racing

[Cajun]

Cajun,

Will a jackplate on an aluminum boat do much for speed or is it primarily for shallow running? Is there a hub available to run this yamaha prop on a V4 OMC (13 spline, 4.25")?

Thanks

The jackplate is primarily to allow you to raise the engine. They were designed for shallow marsh fishermen. The speed gains are moinimal and a byproduct of raising the engine. I think they sell a yamaha black painted stainless for that will fit the V4.
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