About to finally take the ACME plunge, just need a little push

[mabbore]

I got a few small dings in my factory OJ 12X12 1' LH prop late last year, and rather than drop $100 on repairing it I am going to finally get an ACME. I know this has been debated to death a 1000 times, but I just want some more input to make sure I spend $400 in the right direction.

I mostly wake skate, wakeboard, but do some slalom at ~30mph. This summer I really want to do some surfing, and I need to re-prop if I want to do that. I am in between the ACME 913 (13X10.5 ) and the ACME 543(13 X11.5). I called Acme and nettle, both seemed to push me toward the 543. My concern is that the 543 might not be enough to surf on, especially for my meek 240 hp PCM. I have some hours on it as well ~800, they are very well cared hours, but none the less.

If anyone has a similar setup, please chime in.

[foxriverat]

I have a practically new acme 541 in the classified if that would work for you 13 x 12 1` LH I used it 3 times end of last year and didnt like it cause it made the hump harder to cross at slalom. All I do is slalom. Since your local I could do $300 since I wouldnt have to ship or pay paypal fees. http://www.ski-it-again.com/php/skiitagain.php?endless=summer&topic=Search&category=Propeller&postid=31780

[Jetlink]

He has the 1.23:1 transmission I believe while you and I both have the 1:1, the rotation is opposite.

[foxriverat]

He has the 1.23:1 transmission I believe while you and I both have the 1:1, the rotation is opposite.

I was going by the dimensions of his old prop that he posted 12 x 12 1' LH

[mabbore]

I was going by the dimensions of his old prop that he posted 12 x 12 1' LH

No you are correct I do have a 1:1 transmission. But the 12X12 is too much for the ballast I want to run. Thanks for the offer though.

[foxriverat]

No problem. My Acme 541 is 13 x 12

[SquamInboards]

My two cents would be to go with the lower-pitched prop that you're considering. The only downside will be lower top speed (doesn't sound like that's your goal) and the fact that, if you're propped to handle weight, you *could* over-rev the engine with light loads. That is, if you aren't paying attention, or don't have a working tach, OR if you have any heavy-handed friends who like to floor it. Especially with older boats, I have found that the Acme recommendation comes in just a little under what they truly expect for WOT RPM. So if they're saying the 543 will run ~4400 @ WOT, I bet that it will come in just a little under, especially by the time you put a couple people and some gear in the boat. My guess is both places are shying away from the 913 because they think it will run over 4400 @WOT. And if you're surfing, wakeboarding, etc more than skiing, I think you'll be happy with the 913. It will still pull a skier at 30, too.

Part of the reason this has been debated to death is that very few boats are exactly alike in construction, power, and usage. Once you DO get a prop, be sure to get a good water test and post your results on the Prop Specs Sticky thread (https://forum.supraboats.com/showthread.php?15325-Prop-Specs-ONLY) so it's another reference point for future people in your position.

[Moor]

I switched last year from the stock OJ prop on my 88 SunSport to the Acme 541 and was very happy with it. I run a lot of ballast for surfing and it pulls like a freight train, and the boat still hits 40mph with ease, but i have the 330hp 454pcm. Maybe a step above the 541 would be good for you since you plan of running a lot of ballast?

[foxriverat]

My comp that I ran the acme 541 on is 310hp. Although it was smoother then my oj 13 x 13 I think the 541 13 x 12 slightly raised the rpm`s because of the 12 thrust. Thus making my hump a tad bit harder. Which is better for wakeboarding. But I was looking to make mine softer for slalom. So I went back to my oj 13 x 13

[cadunkle]

Can't really add any value for a smaller lighter boat with a 351 but my inclination would be to lean toward more pitch than less. On my Saltare with 454 I went from factory cast OJ 14x13 to an Acme 13x12 and I wish I went with the 13x13. The CNC prop definitely hooks up better, but the 454 has enough torque to push more pitch. The OJ 14x13 would do 48 MPH easy and I've seen as high as 50 on GPS. The Acme 13x12 is more like 43-44 MPH. I notice with the CNC Acme there is more torque on the steering wheel, it definitely has more surface area and pushes more water over the rudder than a cast prop.

My engine has been rebuilt by previous owner with unknown build but has an aluminum intake and larger carb. I tend to see the answer to lack of performance being more power not more gearing. I like to maintain higher torque at lower RPM for more economy and less wear while still achieving better acceleration. I went with a CNC prop to have more surface area, reduce slip, and increase efficiency. Not scientifically measured but I think fuel consumption at riding speed, 22 MPH, lightly to moderately loaded may have slightly decreased. The last time I accurately measured at the end of last season was not riding but just cruising around and the boat only did 2.6 MPG and 8.5 GPH. I did notice a dripping secondary booster this past weekend when getting it ready for the water and lowered my secondary float level to correct that. May have been an issue last season too as I recall seeing 6-7 GPH previously.

[CornRickey]

just ordered mine about 20 minutes ago so there is your motivation! Went with the Acme 1617 through Wakemakers. Wakemakers is cheaper than Nettles right now due to free shipping and no tax. Plus it will be here in two days!