Advice for New Prop on 2000 Four Winns

bpitts

Recruit
Joined
Jul 15, 2009
Messages
3
Iboats,
I recently purchased a used Four Winns ski boat(details below). We live on a fairly small(250 acre) lake so speed is not important to me. We use the boat 100% of the time to pull skiers, wakeboarders, tubes, etc. My problem is when the boat has more than four people on it, it is very hard to pull up an adult slalom skier and the boat is not easy to plane. I believe it is a prop issue but I wanted to see if anyone could help me. Would a four blade lower pitch prop along with a Cobra Edge hydrofoil help?

Boat Specs:
-2000 Four Winns Horizon 180
-LOA 18 feet, Beam 8 feet, Deadrise 19 degrees, Weight 2200 lbs
-Boat holds 32 gallons and we usually have 6 to 8 people on board
-Boat is used only for skiing, wakeboarding, and tubing
-Volvo Penta 4.3GL, V6, Year 2000, 190 HP
-Manufacturer's Recommended WOT Range is 4200-4600
-Does not currently have a hydrofoil though I am considering adding one
-3 Blade Aluminum Prop, 14 1/4 x 23, Not sure of Make but # is 3850303
-WOT RPM and speed from Prop: 4000 RPM, 4 People in Boat, 18 gallons of gas, and top speed of 37(I did not trim the prop up at all during the test)
-Sea level
-Boat does not pull up adult slalom skier or wakeboarder very easily with 6 or 7 people in the boat. I would sacrifice as much as possible on the top speed to get better holeshot, etc to get skiers up.

Thank you very much for your advice.
 

robjen1019

Petty Officer 1st Class
Joined
Apr 18, 2007
Messages
257
Re: Advice for New Prop on 2000 Four Winns

I would drop 2 prop sizes, and possibly try a 4 blade. 23 is quite a lot of pitch for what you are using your boat for. A 19 will raise your rpms by 600 to 800 rpm, and the 4th blade will drop about 100 or 200 rpm which would put you right on 4600 rpm.
Ive had really good luck with the solas 4 blade amitia props. They provide pretty good stern lift on my 19.5 sunrunner which gets it on plane faster when pulling toys. The four blade also helps when going in reverse. They run a little over $100 and Iboats has them in stock.


oh, one more thing, forget the hydrofoil and get Nauticus Inc. Trim Tabs. I have the plastic ones on 2 of my boats and love them. With the hydrofoil, when turning corners the boat can get tipsy. The trim tabs are automatic and adjustable to the amount of lift your boat needs.
 

hwsiii

Commander
Joined
Jan 25, 2009
Messages
2,639
Re: Advice for New Prop on 2000 Four Winns

B, I would buy a 20" pitch prop it will raise the RPM right at 600 and then you lose about 150 RPM for the fourth blade, which means a net gain of about 450 RPM to 4,450 RPm with 4 people on board and it should not exeed recommended RPM with only 1 person and will keep your top end speed very close to where it is now. Below are the numbers for the prop change and the prop.

Prop Change

bpittsPropChange.jpg



Vortex Prop

Price: $132.55
You Save: $56.44
Compare: $188.99
Discount: 29.9% Off


Propeller Specifications:

SKU:prop #992204Hub #105
Manufacturer: Michigan Wheel
Brand: Vortex XHS
Material: Aluminum
Diameter: 14?
Pitch: 20?
Blades: 4

Another advantage to buying this prop in my opinion is that if you decide to buy a stainless steel prop later this will be easier t sell, because it will fit many boats just by changing the hub out. But it is your decision.



H
 

bpitts

Recruit
Joined
Jul 15, 2009
Messages
3
Re: Advice for New Prop on 2000 Four Winns

Hey guys,
Thanks for your help with the prop. It looks like if I could go to a 19 to 20 pitch 4 blade without exceeding the WOT range, I would be OK. I may have incorrectly calculated WOT, though. I did not trim the motor up at all during the WOT test. Under normal load/conditions, I pushed the throttle all the way down, waited for the boat to plane, and recorded the WOT of 4000 rpm. After the boat is on plane if I trim the motor up, the WOT goes up by 500 to 600 rpm. Did I correctly calculate the WOT or should it be the max rpm with the motor trimmed up?
Thanks again for your help.
Barry
 

hwsiii

Commander
Joined
Jan 25, 2009
Messages
2,639
Re: Advice for New Prop on 2000 Four Winns

B, we needed the maximum RPM at WOT trimmed up, but i will recalculate and see what the numbers are.

H
 

hwsiii

Commander
Joined
Jan 25, 2009
Messages
2,639
Re: Advice for New Prop on 2000 Four Winns

B, I wouldn't go any lower than a 21" pitch and when you are lightly loaded you will need to watch how much you trim the motor out so you don't exceed maximum RPM. Any lower in pitch and it will be too easy to exceed the maximum RPM, but the four blade will definitely increase your hole shot and acceleration. And let me commend you on your getting all of the information to us as right as possible the first time. Don't buy the hydrofoil, it is not needed for your circumstances.


H
 

bpitts

Recruit
Joined
Jul 15, 2009
Messages
3
Re: Advice for New Prop on 2000 Four Winns

H,
Thanks for all of the advice. You nailed it. My dealer let me borrow a Volvo Penta 21 inch 3 blade aluminum prop. Max RPM on Full throttle planed increased to 4600 which is at the top end of the recommended range. Your program is obviously very accurate! Will try slalom tonight to see if holeshot improved. If not enough, I will order a 4 blade 21 inch as you recommended. Thanks again!
B
 
Top