Same ol more holeshot!

[bbfrs1]

I have a 1990 Bayliner Capri with a 1985 Johnson 115hp. Motor runs great! Has a Solas Rublex 13.25x 17 aluminum prop. With my wife and 2 kids, dog, and fishing gear it runs 5100 rpm at 35mph. My question is how to get more holeshot? I can get her up on 2 skiis but not on 1. Should I do a 13x15 3 blade or try a 4 blade?

 

[craze1cars]

Re: Same ol more holeshot!

The closer you can get it to 5,500, which I believe is the max for that engine, the better your holeshot will be.

A 15 pitch is definitely in order, if you want to try pulling up on 1 ski. 4 blades usually helps a bit as well, compared to 3.

 

[SparkieBoat]

Re: Same ol more holeshot!

4 blade will lower your RPMs by about 200 over a 3 blade same pitch. Now this can vary widely depending on manufacturer and other prop differences. a 15 pitch 3 blade sounds about right, the 15 pitch 4 blade should put you around 5300 which is ok. you may lose some top end though. Trim tabs can make a huge difference in hole shot and planing faster and at lower RPMs, if you spend your money on trim tabs you may find that your 17 pitch prop will get more RPMs. also you might try raising your motor a couple of holes where it bolts to the transom. the higher you can get it without cavitation the better.

 

[bbfrs1]

Re: Same ol more holeshot!

I have Nautilus ST tabs on it now. They helped tremendously, before she had to eat a lot of water before she could get up on skiis. I also have a whale tale that I was going to put on, but my dealer said if they helped so much they would already have them on. So I have been hesitant. Anyway so you think the 4 blade 15 pitch would be the best way to go then. Im really not worried about top end.

 

[SparkieBoat]

Re: Same ol more holeshot!

you may want to get a 4 blade 13 pitch just for pulling skiers, make sure to watch your RPMs and keep them under 6000, then use your 17 when you are fishing or just riding.

 

[Texasmark]

Re: Same ol more holeshot!

If you are happy with everything else but hole shot I guarantee you, porting the prop or purchasing the identical prop ported will solve your problems.

Porting is nothing more than drilling a hole just behind the leading edge of a blade on the prop. Location and size are governed by a lot of things.

I just took a SWAG and drilled a 1/4" hole about 1 1/4 below and behind the leading edge of my Ballistic SS prop.

What it does is to allow exhaust gasses to flow over the next blade coming up the revolution and in doing so, it relieves the tremendous pressures associated with "coming out of the hole"
So, I get the best of both worlds.

HtH

Mark

 

[glengold]

Re: Same ol more holeshot!

If you are happy with everything else but hole shot I guarantee you, porting the prop or purchasing the identical prop ported will solve your problems.

Porting is nothing more than drilling a hole just behind the leading edge of a blade on the prop. Location and size are governed by a lot of things.

I just took a SWAG and drilled a 1/4" hole about 1 1/4 below and behind the leading edge of my Ballistic SS prop.

What it does is to allow exhaust gasses to flow over the next blade coming up the revolution and in doing so, it relieves the tremendous pressures associated with "coming out of the hole"
So, I get the best of both worlds.

HtH

Mark

Hi Mark, I was hopeing you would be able to post a picture of this prop mod. I've seen ported props from the manufacture's, just curious how you did it.

Thanks-
Glen

 

[SparkieBoat]

Re: Same ol more holeshot!

porting your prop can work..I would recommend using a prop shop to do it though. Mark obviously knows what he is doing, but you could easily ruin your prop if you dont.

 

[bbfrs1]

Re: Same ol more holeshot!

I have looked into these before. I was going to buy a Turning Point Huster 13.75x15, but I thought that they sounded too good to be true. So I went w/ the traditional. However if really works that well, I think I will try them out, iboats has them for $100

 

[Texasmark]

Re: Same ol more holeshot!

I can post the picture. In the mean time, Having run several of them I knew what to expect. Additionally, I pulled up the OMC picture that is popular on here and it was not right for my application.

Your best bet would to buy a ported "new prop" when you buy it. Second would be to go to a prop shop and have them do it if you find a non-ported prop you think you'll like and after trying it decide to have it ported.

In porting things to consider are prop ribs that can get in the way, where to put the hole with respect to the blade, how large a hole to drill, and having a suitable drilling machine with proper fixtures to hold the prop and drill through the nickel (tough stuff), and each hole should be in exactly the same place with respect to that blade to prevent uneven rotation or vibrations from non-uniform loads on the blades and all.

Yeah, I never drilled one before, but was careful, and was lucky I guess. Got it right the first time.

There are plenty of ported props out there. Since you aren't worried about top end the 4 blade non-ported could work, but again, the thing I like about ports is that it unloads your engine at the highest stress point......when the boat is in the water and the skier is in the water and you are trying to get the engine to spin the prop to get you going. Porting just takes the pressure off the engine, allows it to spin up faster, developing it's hp faster and the result is a much quicker hole shot. It just works......and once you are up and running, it just goes away,like it never existed !!!!! You don't have to buy that extra blade in the first place, and don't have to lug it around with you all the time (top end losses) either.

Thanks,

Mark

 

[Texasmark]

Re: Same ol more holeshot!

Hi Mark, I was hopeing you would be able to post a picture of this prop mod. I've seen ported props from the manufacture's, just curious how you did it.

Thanks-
Glen

If this comes through, here is the ported prop, 2 pics: A shot of the 1/4" hole (1 per blade, 1 1/4" from the front of the hub and 1 1/4" down from the leading edge of the blade.....not my first choice in location, but there was a prop rib where I wanted to put one of them but they all have to be in the same location to the respective blade and this works....so why quibble about success...grin. On the other shot you can see more of what the prop looks like (the rear of the blades come squared off as you see them....a Ballistic trademark), my standard trim tab with the front edge shaved off (I wanted all the tab I could get so I didn't use the Merc narrow one), and finally shot of my stepped hull that allows me to get 50 mph and the narrow wake you see in my Avatar from my little 90.

I pulled down the instructions from the site and followed them....not bad, nice and simple....looks like they did a good job on their new software....we'll see.

Mark