PROP PITCH
- Thread starter Piston1
- Start date
Help Support Intlwaters:
Hammerhead
Well-Known Member
- Joined
- Apr 5, 2002
- Messages
- 1,680
That question needs to be a little bit more descript. It of course, depends a lot on what kind of engine, boat, and set up you are using. Weight, and CG are important as well.
Please describe what you will be running, then it will be easier to say if it is even possible at all.
Hammer
Please describe what you will be running, then it will be easier to say if it is even possible at all.
Hammer
Piston1,
You will need aprox. 6" of pitch for 67 or 80 motor.We run
5.8" and 5.9" into the 90's.The V-967,V955,or V947/3 all
are possible to take you into the 100MPH bracket.Andy
just posted the 2170 is also making it into the 100MPH's.
You just need a GREAT MOTOR,good setup,and some
good props to get you there.The aero. at 100 MPH is HUGE
to overcome.I have seen alot of people get into the 90's
but not 100 MPH.You need to cut down the 2170 to 63 mm.
Good Luck, :
Mark
You will need aprox. 6" of pitch for 67 or 80 motor.We run
5.8" and 5.9" into the 90's.The V-967,V955,or V947/3 all
are possible to take you into the 100MPH bracket.Andy
just posted the 2170 is also making it into the 100MPH's.
You just need a GREAT MOTOR,good setup,and some
good props to get you there.The aero. at 100 MPH is HUGE
to overcome.I have seen alot of people get into the 90's
but not 100 MPH.You need to cut down the 2170 to 63 mm.
Good Luck, :
Mark
Tom v.d Brink
Well-Known Member
- Joined
- Dec 25, 2001
- Messages
- 143
Good question and definatly one i'm working on myself (or at least i'm trying to do 90mph in europe with a .45)
but I disagree with hammer's answer.
I think in the case of wanting to run 100mph you need to start at the prop and adapt the rest of the boat to that.
I think this should be the way because there are not many props with a potential of pushing a big boat forward at 100mph. so with limited choice that's the starting point. work on the setup and the engine for things to work with the prop you think best and easyest capable of atchieving the speed you want.
Andy indeed pointed out the V967/3 and the 2170 (cut to 63mm) as good props to use. so with his runs at 126mph I would believe him and use those props.
Now something else you asked about was prop efficiency (as I normally call slip).
on the calculations i make i usually come out between 55% and 60% never better than 60% I think it's not possible to go better than that.(so for you people talking in slip 30 to 45% slip)
Tom v.d Brink
but I disagree with hammer's answer.
I think in the case of wanting to run 100mph you need to start at the prop and adapt the rest of the boat to that.
I think this should be the way because there are not many props with a potential of pushing a big boat forward at 100mph. so with limited choice that's the starting point. work on the setup and the engine for things to work with the prop you think best and easyest capable of atchieving the speed you want.
Andy indeed pointed out the V967/3 and the 2170 (cut to 63mm) as good props to use. so with his runs at 126mph I would believe him and use those props.
Now something else you asked about was prop efficiency (as I normally call slip).
on the calculations i make i usually come out between 55% and 60% never better than 60% I think it's not possible to go better than that.(so for you people talking in slip 30 to 45% slip)
Tom v.d Brink
