prop tricks

[crazyray]

have heard that if I drill small holes thru prop hub to allow exhaust to get to prop blades that it will allow better holeshot... without giving up anything on topend.....is this true....how big of holes... where at on prop hub ie. how far from leading edge of blade...thanks guys.

 

[Dhadley]

Re: prop tricks

Very true! Everything depends on where you are now with what prop. What set up? What rpm are you capable of now? What X dimension are you at now? What boat design? What motor?<br /><br />Good luck!

 

[River Rat 01]

Re: prop tricks

Check out turning point propellers.com<br />they have high perf aluminum and 2 different<br />perf level SS props. They are a 2 piece prop,<br />I've only had mine for a month or so, but I<br />love it. Also it's a cupped prop, so go with<br />2" less pitch. They also have a listing of<br />dealers by state. Good Luck,<br /> R R 01

 

[crazyray]

Re: prop tricks

Well I took my 19"cupped SS prop drilled three holes 1/8" dia. about 1" from leading edge of blade.....figured if didn't like it could plug with set screw or such......WOW what a difference... made pulling up a skier on slalom much easier.....and seems to be no lost speed or extra rpms on top end.....Worth the experiment

 

[kansasmike]

Re: prop tricks

I just got my Turning Point prop and had no idea why it had holes in the hub. I went from a 19 oem OMC to a Turning Point 17. Wow is right! I feel like I went from 130hp to 150hp. It still has good top end speed. I bought it mainly because of the great price and free hub kit offer. I'm telling you if you're in the market for a prop don't overlook these guys!

 

[BirdChaser]

Re: prop tricks

Can someone explain why this works? Will it work on most all motors? Is there any applications where it should not be done?

 

[clanton]

Re: prop tricks

Sucks air and slips a little allows engine to get into powerband quicker. I think DUNK could write a page on this.

 

[babes@sledbabes.com]

Re: prop tricks

We see replies that mention the holes being in the hub and the blades. Which is correct or both? We checked out turning point and didn't see holes on the blades at the web-site or are they too small? This is interesting to us is there more info on this "hole deal" (pun)

 

[crazyray]

Re: prop tricks

holes are thru hub to let a little exhuast to get to the prop blades....lets it slip a little at low rpm....

 

[SMURPHY]

Re: prop tricks

Please Clarify, where exactly do you drill the holes?<br /><br />Shawn

 

[crazyray]

Re: prop tricks

well can only say what worked for me......I drilled the leading edge of hub about 1" from lower unit. Three 1/8" holes one in front of each blade...straight into the exhaust passage in center of prop....made a real difference on my boat......good luck

 

[babes@sledbabes.com]

Re: prop tricks

We tried this tonight on our 1991 Evinrude 70 VRO that is on a 16 ft tri hull. WOW...big difference...very noticable. Hit the power range very quickly and planed right out. Very good info, <br /><br />Thanks,<br /><br />Dona from: www.sledbabes.com

 

[corm]

Re: prop tricks

here is a link that shows where to drill the holes. Merc uses a set of plugs to change the size of the hole which allows controled cavatation for faster aceleration with high rake props. Most holes that I have drilled have been 3/16th to 5/16th" depending on the<br />boat and usage. I had one boat set up that took a 1/2" hole to get it to work right,rather large! http://www.mercurymarine.com/cgi-bin/mercprod/MercuryHome/Templates/bassfishing.jsp <br />Look at the trophy prop.<br /><br />corm

 

[corm]

Re: prop tricks

<br /><br />Hope this works better .......corm

 

[Big Four]

Re: prop tricks

When you punch the throttle you get a blast of exhaust from the engine. Before the boat starts moving fast(er) there is actually a pressure inside your prop because it's full of water. This water in your prop hub creates resistance and the exhaust air it blown out the holes over the face of each trailing blade. Air on the blade face lets it slip,(ventilate) same as slipping a clutch on your truck to pull a heavy boat up a ramp. This gets the rpm up so she has more torque. After the boat is on plane and moving the prop hub is actually under a vacuum. As the boat moves through the water it actually pulls the exhaust out of the hub and it stops pushing air out of the holes. This is why it only works at slow speed where you need it.<br /><br /> As in the pic Corm posted you see the hole just behind the leading edge of a blade. As the prop spins this hole feeds the following blade the air. This work is best done by a prop shop. Once you get a small set of holes punched the prop guy it's not hard to enlarge them yourself a 1/16" at a time. I'd go real easy on how much and fast to increase size. Each size should be tried with different loads in the boat.

 

[prplhze65]

Re: prop tricks

HEY,CORM, THE PROP IN THE PIC. WHAT DOES ONE OF THOSE COST?

 

[kevlar3000]

Re: prop tricks

350 .00 or so

 

[alpapale]

Re: prop tricks

Hey guys I got one of those hustler aluminum props. Great hole shoot and immediate throttle response but I got a vibration at 2800-3000 rpm. Also, I seem to notice a vibration during low speed turns. The guy at Turning point propeller said maybe I need to reseat and re-torque the prop. He also said I could be feeling a pulse sensation due to these vents. Does anyone feel what I feel with this prop??

 

[alpapale]

Re: prop tricks

I just learned that my 2001 Volvo-penta does not have through the hub exhaust. Insted the exhaust is routed to ports just below the anti-cavitation plate. What then are these holes in my Hustler Turning point prop doing for me if anything? Do they hurt?

 

[paddy87]

Re: prop tricks

Does anyone know if this works on smaller motors, say a 50hp merc.