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Matt Glenn
01-12-2011, 09:48 AM
Do you guys Know if the prop changes the ski wake any or just the hole shot. Just wondering beacuse when I bought my boat the guys talked me in up grading my prop to a 3 blade, I could not tell you what the prop is called ( 2006 outback) I'm just wondering now if the wake could be any better with a different prop, now I look back and I those guys I bought the boat from don't even ski

kaneboats
01-12-2011, 10:07 AM
I would give Eric at OJ a call and give him all your specs. He'll help you pick the right one for what you do and usually exchange it if it's not what you want. Good luck!

maxpower220
01-12-2011, 05:00 PM
A 3 blade and a 4 blade can (and usually will) change your wake. Holeshot can also change. However, there are many factors to that, size, cup, and pitch of either. IMO, it is best to speak to a maker (OJ or Acme) about what will be best for your application. "Best" wake for slalom will be rider dependent, some prefer 3 blade, some 4 blade. Also remember that just because a MC boat has a "better" wake with a 4 blade, doesn't mean that your boat (or any other) will.

jasonwm
01-18-2011, 06:24 PM
Although a prop swap can profoundly impact a number of performance characteristics, unfortunately wake size and/or quality will not be impacted enough to tell a difference. It's possible in a direct back-to-back comparison you could determine a difference in the wake quality between two (appropriate) props on the same boat, but outside of those strict conditions you'll never be able to tell a difference from the end of the line.

zabooda
01-19-2011, 02:49 AM
Three blade has a less prop wash and higher top end speed but a worse hole shot. There are discussions in years past. I would like to go to a three blade the next time I need to replace a prop. Knock on wood as I've gone nine years without a mark on my prop.

kaneboats
01-19-2011, 10:00 AM
Although a prop swap can profoundly impact a number of performance characteristics, unfortunately wake size and/or quality will not be impacted enough to tell a difference. It's possible in a direct back-to-back comparison you could determine a difference in the wake quality between two (appropriate) props on the same boat, but outside of those strict conditions you'll never be able to tell a difference from the end of the line.

You can see a big difference in your surf wake just from changing props. Not so sure about the characteristics at 80 ft and with full ballast, but at surf speed there's a noticeable difference.

cmtaylor777
01-19-2011, 12:50 PM
Talking strictly surf wake......Would it be worth it to switch from a 3 blade to a 4 blade to incease wake hight or to clean up the wave?

kaneboats
01-19-2011, 08:01 PM
I don't know enough about your boat or setup to have an opinion. zegm might be a good person to ask as he went from 3 blade to 4 for skiing but they also surf so he might have noticed something there.

jasonwm
01-20-2011, 06:31 PM
Three blade has a less prop wash and higher top end speed but a worse hole shot. There are discussions in years past. I would like to go to a three blade the next time I need to replace a prop. Knock on wood as I've gone nine years without a mark on my prop.
Unfortunately with all of the variables that can change from one prop to a next there is no way you can make a blanket statement about a three blade versus a four blade. That goes for performance, fuel economy, speed holding and any changes to wake size or shape. There's just too many factors at play to isolate the impact on one particular category. And how do you determine what a comparable three blade and four blade prop are? Are they identical in terms of the major measurements (never mind that those only tell a portion of the actual geometry of the prop), or is based on the props that are most similar performance wise?

My point is that you just can't make a blanket statement like that, just like you can't say a car with an eight cylinder engine will be faster, or have worse fuel economy than a car with a six cylinder car. Sure, there are situations where that's correct, but there are also some six cylinder engines with more than 100HP/cylinder that in a light car will have very impressive acceleration.

The same is true for props, so spending $350+ just to eek out a very minor improvement in the quality of the wake really strikes me as a waste of money. Instead, buy the prop for the performance you need, whether that's hole-shot for surfing and wakeboarding, or top speed for skiing and barefooting. That's where different props are designed to show an improvement, and whatever resulting wake changes that come along with it will be incredibly minor.



You can see a big difference in your surf wake just from changing props. Not so sure about the characteristics at 80 ft and with full ballast, but at surf speed there's a noticeable difference.
All of our experience has shown us the opposite is true. Sure, there's a chance you may get a perceived benefit from a particular prop, but how do you actually measure that, and what happens if it's not the right prop for maximizing the performance of the boat (which is the props real purpose)?


Talking strictly surf wake......Would it be worth it to switch from a 3 blade to a 4 blade to incease wake hight or to clean up the wave?
Absolutely 100%, unequivocally, without a doubt no. There's just no way to guarantee that, and what happens if you did happen to find a prop that made a significant difference in the wake quality, but the performance of the boat was much worse? If you're using your boat for surfing or wakeboarding almost exclusively then there is a performance improvement to be had from a prop upgrade, but buying a prop just to improve the appearance or perceived quality of the wake is throwing good money after bad IMHO. Spend that money on something we know will make a difference (ie: additional ballast).

All of the above is just my humble opinion, but we've sold thousands of props and done hundreds of tests in different makes and models of boats to determine what works best, so it's based on a pretty big sample size.

Laz
01-20-2011, 07:54 PM
Search for my comments on switching props for an Outback.

zabooda
01-21-2011, 12:12 AM
There are some physical characteristics of the three versus the four blade prop that must be taken into account. One physical difference is total surface area between the two props which will increase drag thus reducing top speed but that added surface area allows for faster acceleration. There are other elements to consider such as diameter and pitch that needs to be optimized based on the power curve.

I originally got a four blade prop thinking I need a good hole shot for my size but I realized after having the boat that I don't utilize the full range of throttle at startup so a three blade would work fine. The prop wash is more than desirable at 36-38 mph where I ski and it would be interesting to see how a three blade would affect it.

kaneboats
01-21-2011, 09:43 AM
I'll tell you that one thing we noticed with our prop testing last year is that when you go to a lower pitched prop the boat obviously gets on plane much quicker when loaded down with surf weight but the higher pitched props actually throw a cleaner surf wake all other conditions being equal. Again, this was just with surf wake and just the ones we tested so it's a pretty small sampling.

rdlangston13
02-14-2011, 10:01 PM
what is a normal speed for barefooting? dont really want start a new thread for this

jasonwm
02-15-2011, 12:49 PM
It completely depends on the person, their weight, experience, and preference. Typical speeds are starting around 35 and going up from there.

maxpower220
02-15-2011, 01:50 PM
Rule of thumb: Body weight \ 10 + 20= speed. 200lb/10 + 20+ 40mph.

Experience, water conditions, etc play a role.

BensonWdby
02-15-2011, 08:34 PM
Agree with MP on foot speed - 10% of body weight + 20 mph. But I know guys that can foot significantly slower once they get it dialed in.

And on a boom I think it is less?? Not sure as I don't foot.

Regarding props: My 1999 Mobius came with a 4 blade OJ. After damaging it I had two different sources push me in the direction of a 3 blade Acme - for slalom. Claimed I would throw rocks at the 4 blade. When I bought the Acme I went right to them, told them what boat/motor I had and they claimed they only had one prop for the boat. So I bought it. Honestly - did not notice that much difference.

rdlangston13
02-15-2011, 10:41 PM
thanks, i had a buddy who said you only need like 20-25 mph. i knew that didnt sound right

maxpower220
02-15-2011, 10:52 PM
thanks, i had a buddy who said you only need like 20-25 mph. i knew that didnt sound right

It is "possible", but that takes a combo of a lot of things. OR you get some barefoot training shoes. They will let you get the basics at around 25 mph. I have a friend that will only barefoot with regular shoes on (not sure that's really footing but), we can lower the speed to around 32 or so.

rdlangston13
02-15-2011, 10:55 PM
thanks for the info. i have no intention or desire to actually try it. i was just curious after what he said. and he is no pro

bergermaister
02-16-2011, 01:13 AM
You should try it at least once in your life - that may be all it takes - good or bad!

I did this (once) when I was MUCH younger on a boom off a BlueWater I/O and if I recall we had to hold about 43mph to barefoot on 7am glass. (6ft3in tall, 200lbs) As gutsy as I thought I was it was scary as he11 hanging out on that boom and dropping in to give it a go. I think my longest run was about 25 seconds. It was the head-toe-head-toe-head-toe cartwheels across the water I remember the most...

rdlangston13
02-16-2011, 10:41 AM
yeah im sure that was funny to watch. makes on hell of a splash too i bet. id have to try it with shoes on first, work my way up to full barefoot

ill try if i had a chance but im not installing a boom on my boat and im not running 43 mph in it either. 350 V8 at 5,000 rpm...no thanks

Mikey
02-16-2011, 09:03 PM
I/We learned many years ago behind a 16 ft Invader with 150hp outboard.We cheated at first wearing running shoes as well. We learned starting deepwater sitting on a kneeboard. It is was one of the coolest sensations once i was able to make a coplete loop/run without falling.
As for the falls ,OUCH. falling at 40mph Hurts big time. We eventually learned there is even a correct way to let go to minimize the end crashes as well.
OH the good old days!!!!

BensonWdby
02-17-2011, 07:56 AM
ill try if i had a chance but im not installing a boom on my boat and im not running 43 mph in it either. 350 V8 at 5,000 rpm...no thanks

Booms are pretty quick to install and remove. They are not a permanent install.

bergermaister
02-18-2011, 07:13 PM
I was pretty paranoid about taking a twig through my foot or ripping a toe off on something but the guy who was schooling us said you really won't feel anything little hitting you going that fast over the water - and we didn't. Shoes would have been interesting though.

I couldn't have done it without the boom AND of course the super padded wetsuit...