prop help

I am just wondering if someone can help me to decide which prop to order.

I have a 1999 alumacraft magnum 165 with a 1999 40 hp merc 4 stroke on the back and a 6 inch manual jack plate. Right now I have it fully loaded with a 24 volt bow mount trolling motor, a 12 volt back trolling motor, 3 batteries, 2 sonar units, 6 rod holders, 8-12 rods, a whole compartment full of tackle, net, all the normal safety gear, a 20lbs anchor with a 5lbs chain and 100' of rope, a minnow trap, all my rain and cold weather gear, and the bait and lunch coolers. I also have my partners gear with me usually.

I am running a 12 pitch aluminum prop that has been fixed up a few times and am running at the perfect rpms with this prop and hitting 25mph gps speed with all this gear and 2 of us in the boat.

I am just wondering if I should switch to a 12 pitch 4 blade or an 11 pitch 4 blade to get a better wholeshot when I have the livewell full and running? I need a new prop so any suggestions are greatly appreciated.

I also realize that I am way underpowered and am just trying to make the best of what I have for now. I could also just stick with ordering the same prop I have but I would like to get on plane a bit faster when I do need the livewell.

Thanks,

Nate

Re: prop help

Just wondering what perfect rpm is.The rating is 6,000.
I think your speed is good considering your load.
No doubt a 4 blade will help your hole shot usually they suggest a one inch drop in
pitch when going to a 4.The Solas amita has done well and been predictable.
Has a reasonable price.Any 4 blade may reduce your top speed slightly.
A 4 will usually stay on plane with less throttle and handle better on plane and at the dock.

Re: prop help

Everything said here is correct to what I've read and heard. I think you should consider mounting the outboard on a set of wedges. They allow the outboard to trim down at a slightly greater angle (4 degrees) and on mine greatly improved my getting on plane without any loss of top end. Just a thought!

Re: prop help

Same prop you have now should be better brand new. Then, if you upgrade the HP, you might be able to use the same prop for better hole-shot... depends on how much more HP you go, though.

If you're looking for better hole-shot without lowering top end, buy a bigger motor

Re: prop help

I am running right around 5800 rpms with 2 guys and the boat fully loaded.

I have an 11 pitch 4 blade comprop but it shoots my rpms through the roof so I don't really want to use it anymore.

Do you think if I step up my prop to a 4 blade 12 pitch I would be pretty good for a better wholeshot and still keep my speed pretty decent?

I just don't have the cash for a new motor right now.

I am planning on entering a few local walleye tourneys next summer and would like to be able to get on plane with me and my partner and all our gear with the livewell full of weighable fish.

Thanks for the help so far and I hope to get some more info.

Nate

Re: prop help

5800 is pretty good with a load but I think if you go to a 12" prop it will help your hole shot but further reduce your rpm a 100 or so.As far as the speed result
its probably a toss up. The 11 will jump up and spin up easier may make up some speed. being a 4 your slip will be reduced may help reduce any loss.
We know you'll lose some rpm with the 12 so even with better slip numbers(?)
your speed will likely be less.
Before a prop selection check the motor height.The antivent plate just above the prop should be about even with the bottom of the boat.Should be visable on plane.A 4 blade will allow the most height.If you can gain 2" it could result in more speed.and a slight improvement in hole shot.

Re: prop help

I have the motor mounted to a manual 6" jack plate and have it set for the best possible outcome right now. I just know that I could be doing better with the prop since mine has taken a beating and has had to be fixed a few times.

I could just go with the same prop I have now but if I can get a better wholeshot with a 4 blade then I would rather just order the 4 blade. I can get on plane at a pretty decent speed normally but when I fill the livewell it seems to take my forever to get up on plane. In a tournament situation it just wouldn't be good for me if the winds picked up and we had the livewell filled.

Nate

Re: prop help

go stainless 3 blade look at ballistic props they are made for hole shot a four blade is not always the best choice if you go 4 blade you need to give one size in pitch to keep same top rpm that should be between 5000-5500 for optimum performance may wanna try a 3 blade 14 pitch on for size get your rpms down to keep from overev

Re: prop help

OK, you have introduced some new information. You've now tried a 4-blade 11 pitch prop and see that your rpm get too high. That is to be expected; you ran perfect with the 3-blade 12 pitch. When going to a 4-blade, you normally increase pitch, but what you had on hand to test with reduced pitch, thus increasing rpm way too much.

I realize you want both hole shot and top end. You really can't get both. A 4-blade 12 pitch will yield better hole shot than the 3-blade 12 pitch, but the rpm will increase at WOT, and probably reducing averall speed.

Now, with the live well filled, you say you need better hole-shot. Also, with the live-well filled, your weight has increased, thus increasing drag through the water, so your WOT rpm may be ok with the 4-blade 12 pitch.

Realize, it is all about setting up your boat for a certain situation. Normally, you want it set up for when you are light weighted, thus not having to worry too much about WOT rpm. In your case, you want to maximize your set up when you're loaded for tournament. So, when you're empty, your WOT rpm will be too much. It's just a matter of watching it and knowing your limitation.

Good luck with the information... I hope it helps making with your decision.

Re: prop help

Ya I think I will end up buying the 4 blade 12 pitch prop and run it during the tournaments and while running pretty heavy. If I am running around on a normal fishing day where I don't keep fish anyways I will run a 3 blade 12 pitch. This should make the boat run better in both situations.

Thanks for all the help and I will update when I end up getting a new prop and testing things out.


nate