? motor and prop setup

[TJEli]

Originally Posted by Rich S

You want more air on your prop by the sounds of it so you need to open the holes in the plugs or take them out 1 at a time until you get the proper RPM's stated in a post above. Those plugs allow exhaust to ventilate your prop allowing it to slip which gets the motor up in rpm's to where it has more torque. If you open them up too much it will blow out. Start pulling them out but watch your rpms when you hit the throttle to take off.

Start taking them out one at a time until you can get around 3500 RPM on holeshot. That should be a good range for your 3.0L. You may wind up with them all open but start one at a time. (you should have 4)

I have to run 2 open and one large plug on my Tempest.

-Eli

[REW]

DR,
Pick up a 3 blade 17 pitch and or possibly a 15 pitch prop to use when pulling skiers.

If you go down to a 15 pitch prop - and keep an eye on the tach to prevent over revving, you will be able to pull two dozen skiers out and around the lake.

Also, as you go down in pitch, try to obtain a propeller that is the largest diameter that will physically fit on your motor and clear the cavitation plate. For a hole shot, you are much better off, by going to the largest prop disk that you can, to get a bigger hole to push the boat through the water. Also, as you go down in pitch, you can increase the diameter, up to the point of not hitting the cavitation plate, which will still keep the motor properly loaded.

Remember, a boats motor is loaded by both the diameter and pitch of the propeller. So, the general rule, is that for a given HP, the diameter of the prop goes down as the pitch goes up. The reverse is also true. i.e. as the pitch goes down the diameter goes up.

Remember, skiing does not require speeds much faster than about 30 mph or so, unless you are barefoot skiing. So, if you want a super hole shot, just have a spare prop for skiing that gives you the hole shot that you want at the expense of top speed.

---
Remember barges that push huge loads up and down rivers are using very large diameter props that are almost flat. Not fast but very powerful.
You have a wonderful boat, that is not a lightweight affair. By the time that you are fully loaded and ready to go skiing, you likely have a ton of weight sitting in the water. You need to get a big flat prop to get this weight moving in a heartbeat. By the way, when I say a ton, I mean a ton. You have a 600 lb motor and a 2000 boat in front of it when the rig is ready to ski. That makes for 2600 lbs of weight, plus the weight and drag of the skier that you are trying to coax out of the water.

Good luck
REW

[Verado Eyes]

So taking out the solid plugs will not affect the top end speed at all??
On a 300 vrod what should the holeshot rpms be??
I have a 21p blueprinted Rev 4 and 22p blueprinted Tempest.
The rev 4 has solid plugs right now and the tempest has large ones.
I am new to running a 208 this year so i am not sure about the holeshot and top end performances. Any input?

[wiredog]

Having the plugs out will not affect the speed once on plane. The water going over the prop at speed in effect stops the exhaust from comming out of the holes. Can`t help on the rest, but TJELi should be able to help with the Vrod. Wiredog

[drbrand]

Thanks REW, I do have a 17 pitch 3 blade Mercury Rapture SS prop from my previous boat. I will have to give that a try also and see where I end up.