ventilate the prop

Hello,<br />Question for all of you, how many of you have ventilated your prop, and was it helpful. I've drilled the vent holes near the root of the blades, and I'm just curious as to how the performance diference was, if there was one at all. The engine is an '82 Mariner 90 HP, on a fairly heavy Aquastar 16.5 footer deepV hull. The local Merc guy here said that the hole shot would definitely improve.<br />the prop is a 13 3/4 with a 14 pitch.....I'm also looking for another prop, a 13X15 if anyone has one they would like to sell...<br /><br />The reason I decided to vent the prop is the 90 hp Marinerseems to make all its power right at about 4000-4500 rpm...I've got it propped so it will tun about 5100 WOT...the specs for this motor are 4500-500 so I'm in the ball park..anyways, when holeshotting, the motor will rev to about 3500 at then grab, I'm hoping with ventilating the prop, it will rev up to about 4000, puttin it right into the sweet spot...anyways, Is my thinking logical, or am I going to buy some 1/4" NPT plugs and plug the holes<br /><br />Thanks <br /><br />James

Re: ventilate the prop

definately don't want any protruding pipe plugs at the leading edge of your prop . If you drilled it already you'll have to live with it or weld and grind smooth.

Re: ventilate the prop

If you are losing holeshot bite, venting the prop will only make it worse. <br /><br />What kind of prop do you have? A Ballistic? Also I would think you could use more RPM than 5100. <br /><br />Good luck!

Re: ventilate the prop

Well, the newly vented prop worked really well...from a standing start, when you firewalled the throttle, the revs would hit 4000 rpm and the boat just flew up onto plane, then the motor pulled nicely to 5000 rpm. After removing the the air bleed jets from the carburators, there was absolutely no transition bog from motor......this setup was running sweet until we met an unmarked sand/rock bar.........my newly rebuilt prop is about 6" in diameter now, and the skeg dont look so nice now....funny how quick things happen at 40 mph.