3 Blade vs. 4 Blade Props

[PikeBayCommanche]

I have a 200 Optimax right now with a Merc Trophy 4 Blade Prop and was wondering what is the difference in performance with a 3 vs a 4 blade. Is the 4 blade for top end and 3 for more tourque??

[ChuckN]

I don't know what boat you have, but here's my $.02

I have a Skeeter walleye boat..switched from a 23 pitch 3 blade Laser II to a 23 pitch 4 blade Trophy on my 175hp. More top end, hole shot is ok, slight RPM increase and better bow lift.

The 4 blade is suppose to be better hole shot, but with a heavy load my situation got worse. But overall performance is much improved on plane. It gets a lot better bite to the water on plane.

A 21 Tempest 3 blade is great, most likely the best in a lot of people's eyes for walleye boats. Good hole shot, speed and lift.

I never tried a Tempest, but I should have. I found a deal on a 4 blade as this was also highly recommended for my set-up.

My Laser II prop would blow out on turns and heavy seas trying to get on plane. Not the right prop for a heavy walleye boat...it is more suited for a bass boat.

[PikeBayCommanche]

Yeah I have my Opti on a 19.5ft Ranger VX Bass Boat and it just seems like my hole shot could be a little better. Seems like the bow takes a little long to drop but maybe it is just me. A three blade would not improve that I wouldn't think right??

[Deitz Dittrich]

I believe the theory is that a 3 blade prop has better top end, and the 4 blade has better hole shot.. at least that is what I have always been told.

[Ralph Wiggum]

Quote:

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I believe the theory is that a 3 blade prop has better top end, and the 4 blade has better hole shot.. at least that is what I have always been told.

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I concur.

[Capt. Don*]

I run twin 225 optis and have 3 blade trophys, top end is in the upper 40's but I run long distances and cruise in the low 30's. I found the boat to come off plane if I backed off and got under 28mph. I bought a pair of Merc 4 blades and the result was coming onto plane faster, holding plane at lower speeds and the stern riding higher. All good things except for a couple points, the fuel economy with the 4 blades was not as good, about 2-3 gallons per hour more, the top end was reduced by about 5 mph. Since I typically operate with passengers and travel 70-90 miles per trip I have chosen the 3 blades as my primary props and am more satisfied with the overall performance.

[mamohr686]

If you stick with the same pitch, holeshot should be better with the 4 blade over a 3. While you get up on plane your rpms should be running at about 3500. If they are lower than that you need to use larger vent holes. Larger vent holes alow more exaust to go over the blades creating more slip and your motor will get up to speed faster. Also, if you have a jack plate there is a plate that you can put on the bottom of it to reduce drag and improve holeshot.

[Gadgetman]

Capt. Don nailed it as far as my experience. I have a 19' ProV that has to do all around family service. I was having trouble tubing with the three blade prop that I had. Bought a four blade and it virtualy jumps out of the water and can almost turn on a dime without blowing out. However top end speed has been reduced and gas useage has increased. I only use the 4 blade for tubing/skiing and fishing on local llittle lakes. If I head up to any of the big northern lakes or Canada I put the three blade on as I would rather have better gas mileage than the hole shot and turning performance

[knoppers]

I also have a skeeter walleye boat, and the 4 blade prop I have was supposed to help in hole shot, and for better controll when trimmed out. I can tell you this, I love this prop. my 3 blade props would cavitate, but not with the 4 blade. top end is very good also, 56 on the GPS.

[ChuckN]

I get 56mph also (up from 51mph with the 3 blade) and hit 60mph once with a tailwind before I throttled down in the larger waves..

[sparkyaber]

I have a prop question also. I have a triton FS 190 running a 200 opti with a mercury tempest 23" pitch. (I don't recall the diameter, and the boat is not at my house)

The boat is plenty fast and jumps on plane- even if the motor is trimmed up at holeshot. The problem I have is the prop washing out while cornering, I really have not had a bunch of time behind the wheel, so I have not really played around with the trim and speed. I am thinking more along the lines of when we are tubing trying to make waves to jump etc.

Does anyone have any ideas on what I could do to remedy this problem? trim postion, different prop?

Thanks

[mamohr686]

Sparky,

A 4 blade trophy will run great and will prevent blowout. You may lose 5mph on top end but you should have better holeshot and be able to stay on plane at a lower speed without porpousing. Keeping the motor trimed down and if you have a jackplate moving it lower a bit will also help you with your current prop. One of the best places to buy stainless props is kenyon powerboats out of FL they will ship any SS merc prop for $400 and will exchange a prop if it doesn't work out. I tried to deal on a stainless prop locally and they wouldn't go under $600. Do a google websearch on kenyon powerboats and give them a call. They have been great to me on 2 different occasions.

[sparkyaber]

Thanks for the help. One last thing that I forgot to mention is when the motor is trimmed all the way down it is very hard to steer. I really have to muscle it around. Trim it up a quarter and she steers like a dream.

[Ralph Wiggum]

That's normal.