Offshoreonly.com - Dual down shafts performance

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Quote:

Originally Posted by Quinlan (Post 4798682)

Carter plumbed my drive intake water to exit out the transom. We were going to do like a drive shower placement to spray on top of drives but swim platform brackets were in the way so it comes out the center more.

Imco just said let it spray out inside the helmet and cap the transom plate

Quote:

Originally Posted by IGetWet (Post 4798550)

For comparison sake, my 06 38ZR imco SCX-4s are about 2” above hull bottom. Haven’t gotten a precise measurement on height or how far back they are. They are on ITS boxes. 17.25” 5 blades 18 degree rake. Planes out good with help of 280 k planes but isn’t challenging by any means. In a video that was taken with a go pro mounted in the notch you can clearly see the tip of the lower above the water. My slip isn’t the greatest however, 15-18 percent at cruise. From my experience and shops I’ve talked to the big imcos run the beat when up high out of the water and have a 16”+ cleaver to get around the big bullet and reach the water. There’s also the handling advantage with the cleavers. My boat was set up high to begin with with long sportmasters. 100+ 4 people coolers, full of fuel. 105 light, best so far of 108

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Holy smokes Torey 108 ! That's awesome, i didn't know you made such a big step up in boats and equipment.

Quote:

Originally Posted by outonsafari (Post 4798739)

Holy smokes Torey 108 ! That's awesome, i didn't know you made such a big step up in boats and equipment.

Thanks Dan. Yea life comes at you quick! The Baja is still in WI and we know the new owners well, we were just out on it last weekend actually.

Torey,
What engines are in your Donzi? Are they Whippled 525's?

Quote:

Originally Posted by endeavour32 (Post 4798780)

Torey,
What engines are in your Donzi? Are they Whippled 525's?

Yes whippled 525s. Valve train obviously redone but other than that they’re still 525 guts. Boos did the tuning, run a 4.5” pulley, never on the dyno but should be around 825hp. Imo the whippled 525 is a really good package. A guy can’t help but think what it’d do with NXTs or #6s. The imcos are power/speed suckers but like others say you’ll be out boating not on the trailer!

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38 Donzi with NXTs and stage 2 700s would be comparable HP to your charged 525s and the ones I know of run 105 to 107. So your right in the ball park with them.

Endeavour, I measured my friends drive height. 2007 39 TG 700s with NXTs 17x35s and his drives are 1 inch above bottom straight ahead of drive. Hopefully this can help you?

Quote:

Originally Posted by rvtransport (Post 4799899)

Endeavour, I measured my friends drive height. 2007 39 TG 700s with NXTs 17x35s and his drives are 1 inch above bottom straight ahead of drive. Hopefully this can help you?

Thanks that does help!