How much ballast before you felt you needed to re-prop

[TRBenj]

The 645 is 2003 technology is what I mean. I am sure its newer and functions fine, its just that there is a reason that most of the newer boats have the larger 14.5" diameter props now. They are more efficient. I am running one on my older san with a python and the RPMs across all speeds are way lower than when I ran the 644. The 644 is just the RH version of what you run. I would never go back to the smaller props now that I have had a newer designed big bladed prop.

That explanation is... garbage.

Theres little to nothing different about the "design" or "technology" of the newer props. All of the Acme's Ive played with have similar rake, and a bunch of blade surface area. Theres nothing different about the newest ones.

Its no secret that larger diameter props work better for larger/heavier boats, and thats exactly whats going on here. Check out a prop that goes on a tugboat! It shouldnt be surprising to learn that wakeboard boats are moving to 14" props as people load them down with more ballast. The more blade surface area (partially a function of diameter), the better the boat will come out of the hole- especially with a load.

Correct Craft did the same thing in 1980 when they increased hull clearance on the Barefoot Nautique in order to use a 14" prop. Mastercraft did the same on their Powerslots dating back to the early 80's.

'Taint no new thang.

Its simply a matter of choosing a prop for your specific application. As people go far beyond a boat's intended use (amount of ballast utilized), it should be assumed that the prop will need to be changed accordingly. More weight = less pitch and more diameter. Really simple! I highly doubt theres anything wrong with the 645 design... youre simply using it improperly.

[HS]

On the 645 and 1579 question, is the 645 the Team prop and the 1579 the Power prop referred to (but not defined) in the options listing?

TR: Any thoughts on the 5 blade props coming out from OJ, potentially ACME as well?

TR: should one of the objectives in selecting a prop also be to optimize the rpm range you are running at speed while ballasted and either towing a rider or for surfing? If so, can you describe the target range?

I recently read a post somewhere that when a guy changed to a 1235 prop, his rpms increased as expected but the guy said he was burning less fuel. If that occured, can it be due to excess load on the engine from the prop and ballast that is "relieved" by the change in prop?

Thanks

[gride]

Your prop should be what you use the boat for. If you have to drive the boat a long way after launching then a 14.5x14.25 I have would suck bc youre topping out at around 30 mph. If you just launch, fill sacs, and ride then it's awesome bc it gets on plane and up to speed quickly and holds well. Call acme or an awesome dealer and ask them. But the ones being recommended sound correct.

[TRBenj]

TR: Any thoughts on the 5 blade props coming out from OJ, potentially ACME as well?

TR: should one of the objectives in selecting a prop also be to optimize the rpm range you are running at speed while ballasted and either towing a rider or for surfing? If so, can you describe the target range?

I am not at all familiar with the 5-blades. I do know that more blades = less efficient at higher prop RPM's, but they do pull heavy loads better at low RPM's. I mostly barefoot and slalom a little- so higher speeds and lighter loads than the wakeboarding crowd... so I tend to prefer 3-blades over 4's. If youre ok with trading off efficiency at higher speeds and some top end, then a 5-blade may work even better than a 4.

Gas engines will generally make more power the higher you go up the RPM band, all the way to their redline. The trick is to run an appropriate amount of RPM's (and thus, power) for the application youre using it for. Of course, the amount of power required will vary depending on the discipline- both in terms of how fast you want to be going (wake vs. surf) as well as the type of hull you have and how much ballast youre running. The engine speed required to attain the proper power will vary depending on which engine you have. Lots of variables... and of course, you have to take into account both ends of the spectrum- both holeshot and top end. Trying to get a prop to work acceptably for everything is often a balancing act.

[xrichard]

FWIW, my 2008 210TE came with the 645. I complained to CC and they swapped it with a 1579 shortly after I picked it up and noticed. The 1579 was the "team" prop at that time and that's what the brochure said came with the TE boats. But the early-build 2008 boats were outfitted with the 645.

Unfortunately, the 210 doesn't have room for a prop with a larger diameter than the 1579....even the 1535 won't fit (...well, it will physically, but there is concern that it will sit close enough to the gel coat that it'll cause some erosion. Some have said that it's not a problem). Before I swapped mine, I made a couple of calls to Acme and found its technical advice very helpful...and willing to spend some time on the phone going over options with me.

My recollection is the 1631 is the most aggressive prop for the 210. With the 1579, I can tell you that I frequently need the hydrogate lowered to get on plane. I run around 1800lbs, but if I'm at 1000 (or greater) feet of altitude with more than four people in the boat, it is slow getting out of the water. Even lower, I can have trouble without the hydrogate depending on number of passengers (e.g. 5-7) and their size. My friends' boats generally don't have this issue with similar loads (e.g. older Wakesetter, new B52, newer Wakesetter, older X2).

[bchesley]

TRBenj,

all you did was confirm what I said.

Wether or not there have been bigger props on boats in the past is irrelevent. Having a bigger prop on a wakeboard boat due to ballast is a new thing, hence the latest technology statement. I won't split hairs with you, but if you go with a bigger prop you will be way more happy with the performance of your boat. That arguement has already been hashed out.....

[HS]

From the Nautiqueparts web site, they mention the 1235 is too large for the 210 and can cause gel coat burn: "1235-High performance Power/Pulling Prop (14.5:x14.25"x1-1/8" bore LH) ( For Wakeboarding (Replaces 645) PLEASE NOTE: this prop is technically too large for the 210. It can cause gel coat burn over the long run. Most people risk this and use the prop with out issue. The "by the book" prop is the 1579 if the stock 645 is not enough pulling power. 1579- High performance Power/Pulling Prop, was 1465 now called the 1579. Its a 13.5"x14.25" LH 4-blade prop, .1.125 dia, .105 cup. Direct upgrade for 645 for 210s requiring a LH prop."

So how much clearance is enough? I see from the specs below that going from a 13.5" diameter prop to a 14.5" diameter prop would make the blade 1/2" closer to the hull.


1579 13.50 14.250 0.105 cup 4 1 1/8" LH

1433 14.00 14.250 0.105 cup 4 1 1/8" LH
1847 14.00 14.250 0.150 cup 4 1 1/8" LH

1235 14.50 14.250 0.105 cup 4 1 1/8" LH

Questions for PN:

1. who is using a 1235 prop on an '08 and newer 210? Are you seeing any gel coat burn? What clearance do you have?

2. any body using a 14" prop (1433 or 1837) instead of a 14.5" prop?

Thanks!

[TRBenj]

The 645 is 2003 technology is what I mean. I am sure its newer and functions fine, its just that there is a reason that most of the newer boats have the larger 14.5" diameter props now. They are more efficient. I am running one on my older san with a python and the RPMs across all speeds are way lower than when I ran the 644. The 644 is just the RH version of what you run. I would never go back to the smaller props now that I have had a newer designed big bladed prop.

We dont disagree on what works better or why- but I do take exception to the notion that bigger props are somehow a "new design" or that slightly smaller diameter props are somehow "old technology". That is simply incorrect.

As it was pointed out, the original prop was selected for a specific application- it was meant for a specific purpose (no more than stock ballast) on a specific hull. And yes, hull clearance is one thing to consider. Insufficient prop clearance to the hull will result in gel and glass damage over time. A metal plate may mitigate the risk of damage to the hull, but may not prevent damage to the rudder or rudder port. As a general rule, 10% of the prop diameter is the "recommended" clearance to the hull. Anything offering less than 1" of clearance would make me uneasy.

This is what the keel of our Barefoot Nautique looked like... the '79 (first year) model had minimal clearance (<1/2"), and they modified the hull to accomodate larger props in subsequent years. The rudder port and rudder also had significant damage that warranted replacement.

[bchesley]

I am running a 1272 on my 2001 super and its way too close for me too. I only ran it because my parts guy and I called Acme to ask them what prop to use on my Python. He guaranteed me it would work and that they had sold several with great results. I was seriously skeptical but went through with it on a whim. I was shocked at what a difference it made. I have a stainless keel plate that should prevent any damage to the gel. Probably the only way I can get away with it, but for how well the boat runs, I can deal with a little gel burn on the bottom of my boat.