Props

[jah81592]

Being used to the old OJ legend props I used to own a Ski Brendella Shortline comp. It came with a OJ 13x13 3-blade prop. At that time I was looking to re-prop the boat. After much research and against much recommendation I went with the 4-blade OJ 13x13 Legend. The prop excelled everywhere (definitely not what the "experts" said) on top end, out of the hole, smoother wakes, top speed actually picked up 1mph and handling in tight situations improved. I was completely at a loss and couldn't explain it why the boat reacted this way when everyone said it wouldn't. Obviously this hull design loved the setup and it worked well.

 

Now fast forward to today, again I am looking to re-prop another boat I have purchased (1993 Brendella Pro-Comp). The boat currently has an OJ Legend 3-blade which I am very unhappy with. The initial pull out of the water is soft the handling seems to be soft (just like my other boat) with the 3-blade. At this moment, I believe the current prop on my boat is the culprit thus resulting in my complaints. Either the prop has been repaired (maybe not properly) or someone has changed the cup. Either way something seems a bit off due to too high rpm @ WOT (5100) and just the ill handling in quick maneuvers combined with the initial soft pull out of the hole. Just to make note the engine is in perfect health (compression and leak down confirm such) and transmission is NOT slipping and in great health but the initial pull is soft. So i am at a cross roads once again with a prop dilemma.

 

After talking to JT @ Nettle Props he recommended a CNC 13x12 3- blade. He mentioned this prop is basically a 3 blade version of the old Legend 13x13 4 blade. Basically what he was saying is that the new CNC jobs have much more surface area than the old style props and that performance & characteristics would be very similar to my old 13x13 4-blade legend. I bumped over to ACME's website to look at all the options and found a 4 blade 12.5x12.5 4-blade which should "in theory" give similar results as the 3 blade. Again at the crossroads! So, finally my question is has anyone tried the new CNC jobs on their boats and compared 3 to 4 blade to verify performance and wake characteristics? I have read on many forums only to find MUCH not all of the response is opinion and not definitive information. I am looking towards a Brendella owner who has actually seen the positives and negatives of each design and NOT opinions of what someone "thinks" it should do. Please note I will be receptive to theories brought forth and encourage all response. I am torn and about to purchase both props and test them send the one back that doesn't yield the best performance for my application. I am leaning 4-blade due to the better surface area and handling characteristics but also am open minded to the new 3 blades which JT mentioned are excellent. If I do a comparison test on my boat I will do acceleration test, handling test and finally pics of different speeds and wake characteristics behind a Brendella and maybe even some "bank" videos of the boat at speed with each prop installed. These boats are affordable and people can afford to "tinker" with them so I believe this would be incredible information to have along with the other tests that i have found on the web.

 

Please note that I barefoot ski, slalom ski and two ski. We do very minimal inner tubing, wake boarding or any other sport that requires "big" wake.

[Dacon62]

I have a 2001 Malibu Response with a 325hp EFI Monsoon.

Purchased last summer. It came with a 4 blade 13x13 prop. Not CNC.

Swapped it out immediately for a Acme 515 (13x12) CNC 3 blade.

Improved grunt, smoothness, top end went from 45mph to 47mph at 4900 rpm and my RPM at 34 MPH dropped by 150 to put me in that 3500 rpm sweet spot while pulling a skier. Turns about 3425-3450 rpm while cruising 34 mph without a skier. Am near sea level (if high altitude you may want the 525, 13x11.5) and can say this was a step up and the right move for my particular set up. What JT said is truth. Today's CNC 3 blades are awesome. No need to go 4 blade to get performance...my experience. Couldn't be happier.

[ALPJr]

Call or email Eric at OJ Props for the best advice.

[jah81592]

Thanks for your answer Dacon it really helped. That is the stuff i am looking for. I will make my decision closer to March. Either way i will post results and let everyone know. I still my purchase both and go do some testing.