What prop

[Jason Johnson]

What should I look for for my 14' Alli 90 yammi for power. I am getting conflicting info at home. I need a prop!

[gotboostedvr6]

whats the gear ratio? i thought they were very low

[Jason Johnson]

2-to-1

[Jason Johnson]

the pitch will come with testing, the type and design is what I am baffled over.

[gotboostedvr6]

start with a 23 that would be a good # to start with ... if you want a 19 to test with i have one you can borrow

[Jason Johnson]

I have a 20 yammi, and a 25 yammi, and a merc 25 cleaver (not mine) I just want to know what to look for, with out doing so much experimenting. Cleaver, chopper, ET Light, Triton, Mazco, ect....?

[gotboostedvr6]

you have alight boat with decent power i wouldnt look for a bow lifter and unless your looking for every mph you dont need to run a chopper/ surface piercing prop

[Jason Johnson]

I want MPH, nothing else matters. Here at home I am being told that a small dia. cleaver is best. Then I am being told a chopper 1 is best. This boat is only an extra toy. So far I have $600.00 in the whole rig. It is in very acceptable shape, It looks real good for a 1980 model boat. The motor is a 03. I love it. It runs 65mph so far with a 25 cleaver. I am also building a short 90. With a no holds barred powerhead. I am trying to scare a few locals with V6s. Then I will remove the motor and place it on a sst60 boat. And clean up the last few V6s around here that are still barking. So for now I need a prop. The type and style are what matters, I don't want to go through 5 -6 props on this phase of my adventures.

[RIVERRUMMER 70]

I want MPH, nothing else matters. Here at home I am being told that a small dia. cleaver is best. Then I am being told a chopper 1 is best. This boat is only an extra toy. So far I have $600.00 in the whole rig. It is in very acceptable shape, It looks real good for a 1980 model boat. The motor is a 03. I love it. It runs 65mph so far with a 25 cleaver. I am also building a short 90. With a no holds barred powerhead. I am trying to scare a few locals with V6s. Then I will remove the motor and place it on a sst60 boat. And clean up the last few V6s around here that are still barking. So for now I need a prop. The type and style are what matters, I don't want to go through 5 -6 props on this phase of my adventures.

WHAT RPM WITH THE CLEAVER? PROP SHAFT HEIGHT? WATER PRESSURE AT
W.O.T.? SETBACK ?
STICK WITH THE CLEAVER AND OPTIMIZE THE SETUP, RUN MAX RPM MOTOR CAN HANDLE WITH GOOD WATER PRESSURE.

[Jason Johnson]

This morning I tried going up another 1/2" The rpms went up from 59 - 6000 to 6000-6100, no gain in speed, still good water pressure. will try more height.

[mslayride]

basically i asked the same question with the tohatsu rib,i will be watching for advice in this as i am running 90 hp tohatsu on a 15 ft boat with jackplate

[RIVERRUMMER 70]

This morning I tried going up another 1/2" The rpms went up from 59 - 6000 to 6000-6100, no gain in speed, still good water pressure. will try more height.

WHAT DO YOU FEEL SAFE TURNING THAT MOTOR? 6500?
WHAT IS THE CURRENT PROP SHAFT HEIGHT?
HOW ARE YOU CK'N SPEED? GPS? SPEEDO? RADAR GUN?
IT WOULD BE TOUGH TO SEE 1-2 MPH ON A SPEEDO BOUNCIN AROUND
AT SPEED.
GOOD LUCK AND BE SAFE!:cool:

[Jason Johnson]

today, another 1/2" the RPMs went to 6200, but the boat would not stay lifted. It would start to bounce and get progressivly worse. So I am at the limits of my current set up I beleve. Time to get the short motor built.

I did manage to run 78mph today, Yes 78MPH, How you say? Well I hooked up with a jet boat with a BBC for power, we ran dead up for a 1/2 mile then I started pulling (cleaner water) after we stopped and digussed things he let me know that He ran 78 so I must be flying :) Go figure.

[RIVERRUMMER 70]

today, another 1/2" the RPMs went to 6200, but the boat would not stay lifted. It would start to bounce and get progressivly worse. So I am at the limits of my current set up I beleve. Time to get the short motor built.

I did manage to run 78mph today, Yes 78MPH, How you say? Well I hooked up with a jet boat with a BBC for power, we ran dead up for a 1/2 mile then I started pulling (cleaner water) after we stopped and digussed things he let me know that He ran 78 so I must be flying :) Go figure.

GREAT , SOUNDS LIKE YOU ARE DEF UP ON THE PAD!!! 78 WOW!
IN A 14' THAT IS LOOOOOOOSE BABY!
JETBOAT GUY IS PISSED I BET!
TEAR EM UP AND PUT EM ON THE TRAILER!

[Jason Johnson]

The RPMs have been to 6900 on this motor, I feel safe with it I built it. I was told that I should not go over 6300. I completely balanced this one, fresh bore and bullets. 93 octane only, 145psi compression, raised all ports .080. Thats it. I am building a blow up motor, light rods & pistons ported to hell. high compression, light flywheel, big tuner, and I will attempt to put 3 -2 barrels on it. At the same time I am sending all the same parts out to the pros to be done right, for the next motor. I LOVE this hobby.
I have a $10,000 motor in a 88 mustang, all that is left is the wiring, I am a electrician, I have not touched it in 5 months.:)

[Jason Johnson]

Picked up to 66.5mph today. Motor still high, Rpms at 5800 - 6000. I got a new prop. Cleaver style with a alum hub. Time for some motor. It actually got up too high and floated on me today. But the driving issuses are a thing of the past. I love my boat.