Need more rpm from Hydromotives....Pitch change? Lab Finish?
08-11-2004, 01:36 PM
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Need more rpm from Hydromotives....Pitch change? Lab Finish?
Ran a set of 23 hydromotive Q-IV's today. Water about 1' chop and 1/2 tank of gas (80 gallons) ran 61-62mph at 4400-4450 rpm. Boat definitely felt like it was more out of the water that with the 23 mirage plus props. What would be suggested to get my rpm up to the 5000 range? What would I gain by just dropping a pitch or two? Lab finish?
Thanks
Thanks
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Last edited by powerguy; 08-11-2004 at 01:38 PM.
08-11-2004, 03:12 PM
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Re: Need more rpm from Hydromotives....Pitch change? Lab Finish?
Speed with 3 blades is around 64-65mph at 4800-4900 rpm with same amount of gas. Props are 23 mirage plus. Boat is 336 Formula with twin 454 mag's.
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"All I need are some tasty waves, a cool buzz and I'm fine"
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08-11-2004, 03:58 PM
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Re: Need more rpm from Hydromotives....Pitch change? Lab Finish?
Power, I meet you at Gl`s fun run, you should be on the right track call the people at hydro to see if the 21pitch or 22 could get you 500rpm. I think 4 blades are the way to go, but you may lose 1mph on top end.
That 336 is a beautiful ride.
mark
That 336 is a beautiful ride.
mark
08-11-2004, 05:09 PM
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Re: Need more rpm from Hydromotives....Pitch change? Lab Finish?
The pitch can be reduced 1" which should give you 200 rpm. Other adjustments should give you another 150-200 rpm for a net gain of about 400. That should put you about where your motors need to be. If you have any questions give us a call.
Matt
Matt
08-12-2004, 09:02 AM
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Re: Need more rpm from Hydromotives....Pitch change? Lab Finish?
Originally Posted by masi242
Power, I meet you at Gl`s fun run, you should be on the right track call the people at hydro to see if the 21pitch or 22 could get you 500rpm. I think 4 blades are the way to go, but you may lose 1mph on top end.
That 336 is a beautiful ride.
mark
That 336 is a beautiful ride.
mark
of Lake Champlain and the docks of the Naked Turtle. Hopefully next year G.L can safely navigate the docks and the waves will be 1' chop. Dave
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"All I need are some tasty waves, a cool buzz and I'm fine"
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08-12-2004, 09:04 AM
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Re: Need more rpm from Hydromotives....Pitch change? Lab Finish?
Originally Posted by throttleup
The pitch can be reduced 1" which should give you 200 rpm. Other adjustments should give you another 150-200 rpm for a net gain of about 400. That should put you about where your motors need to be. If you have any questions give us a call.
Matt
Matt
With all that work involved would it be more cost effective to sell/trade my 23's and get another set of 22 labbed or 21's ?
Dave
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"All I need are some tasty waves, a cool buzz and I'm fine"
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08-12-2004, 09:26 AM
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Re: Need more rpm from Hydromotives....Pitch change? Lab Finish?
It depends on how much money you have in the props. If you have a good set, stock and unmolested it would be worth putting the money into them. Keep in mind that a prop that is down pitched will not have the same top end as the same prop that is not down-pitched. The down-pitched prop will have better acceleration than an original prop of the same pitch.
For example; a 22 pitch Hydro Quad IV will be faster than a 23 pitch Quad IV that has been down-pitched to 22. The 23 down-pitch to 22 will have better acceleration than an original 22 Quad IV.
Matt
For example; a 22 pitch Hydro Quad IV will be faster than a 23 pitch Quad IV that has been down-pitched to 22. The 23 down-pitch to 22 will have better acceleration than an original 22 Quad IV.
Matt
