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Drive abuse question

zx14

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I am running 1000+ hp in my 26' Daytona thru a merc xr ITS. 1.39 gears 32" prop 6250 top RPM gets me around 125 mph. That calc to about 8% slip.

If I was to run a 26" prop, all things being equal , I should see a tick over 100 mph, and that would be fine, I assume it should accelerate like a bat out of hell, I know it's heavy, like 4500-5000 lbs.

You think it would put more or less stress on the drive.

I would guess more, if I was to feel more seat of the pants push, it's got to be pushing all the parts harder.

Any experts care to chime in?
 

djunkie

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I would think that smaller pitch prop would put less load on everything. Why do you wanna drop so much in pitch? If you can swing a 32 why not go down to a 30?
 

zx14

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I'm wanting what I can't have. Acceleration like my old 21'

100 mph is more than plenty . We all seem to try to break 100, but truth be told, is more than I need. Yup, I've gotten old.

26' may be up for sale this winter😋
 

BHC Vic

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I'm wanting what I can't have. Acceleration like my old 21'

100 mph is more than plenty . We all seem to try to break 100, but truth be told, is more than I need. Yup, I've gotten old.

26' may be up for sale this winter[emoji39]

I might like that 26 [emoji2]
 

79 HUSTLER

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I was tired of constantly breaking drives so I went from a 34 down to a 26. Still plenty of speed and the drive has lived for seven years now. Definitely not the best top end but also no more breaking two to three drives a season. Tons of torque from the 632" and a heavy 29 foot cat.
 

zx14

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I was tired of constantly breaking drives so I went from a 34 down to a 26. Still plenty of speed and the drive has lived for seven years now. Definitely not the best top end but also no more breaking two to three drives a season. Tons of torque from the 632" and a heavy 29 foot cat.

Thanks, so you can hammer it with the small prop, take off better and th drive likes it?
 

79 HUSTLER

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Thanks, so you can hammer it with the small prop, take off better and th drive likes it?

I roll into it nice and easy still. Then I can lay into it pretty good. My days of hammering the throttle are done in this boat, seven drives in two seasons changes that program.
 

Sigus

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I roll into it nice and easy still. Then I can lay into it pretty good. My days of hammering the throttle are done in this boat, seven drives in two seasons changes that program.
Are you running 1.5 with a 26?

I just redid my motor to 632 and have gobs of low-end torque running 1.5 and will most likey stop at 32. I have heard bad stuff about the 34.
 

BajaMike

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I'm wanting what I can't have. Acceleration like my old 21'

100 mph is more than plenty . We all seem to try to break 100, but truth be told, is more than I need. Yup, I've gotten old.

26' may be up for sale this winter


Lower pitched prop is much lower stress on the outdrive, and on the engine. I have seen lots of busted cranks and ruined engines from guys who over propped their boats to get speed, and they burn up the engine.


Lower prop is much better, just make sure you don't over rev it.
 

BDMar

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Anytime you put a smaller prop on it will put less stress on the drive. However, you keep saying how hard you want it to accelerate, and hammering it with a smaller prop. The hardest thing on the drive is the guy in the drivers seat. If you put a smaller prop on so you can hammer the throttle and feel the acceleration that it seems you want, you'll be breaking drives. Period. I don't think a 26 will work with that boat and the power you say you have. It will more than likely blow the prop away and end up with less acceleration than you have now.
 
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