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Damyankee

Prop Shaft Height

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Need some advice, I am in the middle of a complete rerig of my 96 STV Mod VP and need to know the best prop shaft height for Drags and some top end. The boat came with a 20" motor that I am changing to a 15", I have cut the transom down and will be bolting motor directly to transom. The boat will be used for normal use and will also be used for drag racing and some top end. I will be running a mod 260 (port work SVS brucato PCU) with a 150hp shot of nitrox and a Bob's coned 200 gearcase. I want the best performance to be for drags with top end being 2nd. As I am bolting directly to the transom I only have one good shot at this, any ideas.

Thanks

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I would use the factory transom holes. No need to fill and drill new holes. A jack plate comes in very handy. You can make the adjustments for drag vs top end, and you will have more clearance to tilt up at a beach. As far as I know, the top STV drag guys run a jack plate and as far back as 9". You can even run a 15" mid on a 20' transom with the proper jack plate, no need to cut up the boat.

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Need some advice, I am in the middle of a complete rerig of my 96 STV Mod VP and need to know the best prop shaft height for Drags and some top end. The boat came with a 20" motor that I am changing to a 15", I have cut the transom down and will be bolting motor directly to transom. The boat will be used for normal use and will also be used for drag racing and some top end. I will be running a mod 260 (port work SVS brucato PCU) with a 150hp shot of nitrox and a Bob's coned 200 gearcase. I want the best performance to be for drags with top end being 2nd. As I am bolting directly to the transom I only have one good shot at this, any ideas.

Thanks

Gonna be tough to hit it just right especially if you're gonna run drags and top end? Bob's makes a jack plate that's less than 3 inches. I run two rockets. One with a jack plate and one without. Its a champ mid which gives me around 7/8 inch to play with and I still need to move a little. But if you're determined to go straight to the boat I'd guess around one inch above.

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Thanks

I have heard everywhere from 3/4" to an 1 1/2 " looks like I will shoot for between 1" and 1 1/4". How much top end would the move from 1 1/4 to 1" be? If all else fails I will order one of the short setback jack plates.

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Thanks

I have heard everywhere from 3/4" to an 1 1/2 " looks like I will shoot for between 1" and 1 1/4". How much top end would the move from 1 1/4 to 1" be? If all else fails I will order one of the short setback jack plates.

One inch should be plenty high with the motor bolted to the transom. From what I remember every inch of set back you raise the motor and 1/8 of an inch. So an inch high at the transom is pretty high. but should overall be pretty close

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Thanks All

Bolted it up at 1" if that dosn't work I have been thinking od a way I can build a jack plate with 1" set back. I have all of the Alu plate I will need, I will try it where it is at and if that dosn't work I will clean off the Bridgeport and get started.

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