Prop debate revised

[extruop]

I know I am a newbie.  I know there has been a heap of discussion in the past threads on props for the X-22, but I have read through them and I am throughly confused about props.

I am in Salt Lake and spend most of my time in the mountain lakes (6000 ft.).  I currently have a 3 blade prop that is quite smooth and frankly does close to 50 mph (can that be right?).  I only have one beef.  I have a hell of a time holding speeds in the low twentys with the factory ballast in the trunk full and four or five people.

I am installing perfect pass next week, but I though I would try a 4 blade prop as well.

So I get on the forums and find out that there is a bit more complexity to this prop decision than I thought.  It may be like argueing over which flavor of ice cream is better but what the heck (can you swear on these pages).

What prop should I put on my X-22.  I dont care about top end much.  I would rather have more consistant speed when weighted.

[toyotafreak]

ACME 13 x 11.5 is the starting point. Everybody that's done one loves it. Question is maybe you want to correct for the altitude - that'd be a good discussion to have with the ACME dudes.

SERIOUSLY doubt you're getting 50 with an X. The stock speedo is accurate at one speed and does need to be calibrated time to time. Calibration just involves choosing a speed that you want to dial in on (say 22.5 mph if you're a knucklegragger), then whip out your handheld GPS on calm water and set the boat right on that speed (GPS). Once the message center's in the programming mode (I can never remember how to do that) you just walk the display to match the 22.5 you're driving at. I'd assume there is a similar setup option with Perfect Pass although it's much less necessary. I'd at least check the indicated versus GPS at 22.5 once you get it installed.

Back to props, I bought an OJ stainless in 2003 and have had good luck at least in the area of running it into sand and muck at least twice without any deformation - a NiBrAl prop like the ACME might very well have broke - incidentally, it's supposed to be easily breakable because you really would rather replace a $400 prop than do >$1800 in driveline repairs.

Performance and smoothness wise, I'd only go ACME, but understand the OJ XMP CNC prop is probably great too.

[extruop]

freak,

Thanks for your help.  I called Bill Weeks at ACME.  Nice guy, incredibly failure with the Epics.  Just like you, he told me to do some homework if I wanted the best prop. 

I will head to the lake, check speed and RPM, and call them back. 

BTW, here are couple of other details that might be helpful to include for others reading this thread in the future.  First, Bill said that he has seen all kinds of different variation on shaft size and Right Hand vs. Left Hand props on every model.  Nobody can tell you what you need without getting under the boat and checking things out.  Second,  at a bare minimum you have to know what your top RPM is at the lake you do most your boating at.  And last you have to know all the specifics of what you are running now.  Size, Pitch, Shaft Size, Cup, and Hand.  If you get all that.  The guys at ACME can eaisily recommend the best prop.
 

[toyotafreak]

Best case is to read the markings on your current prop. He's right about the shaft size, etc. (see the "inch and an eighth!!!" thread). BTW, that's for an S22, not an X.

If I were you, I'd beg borrow or steal a handheld GPS and create your own table like this:

Just mapped a few weeks ago (Epic S22, no ballast, full fuel tank, OJ Stainless 4-blade 13x13)

RPM? ? ? ? MPH (GPS)
2000? ? ? ? ? ?9.5
2500? ? ? ? ?17.7
3000? ? ? ? ?24.1
3500? ? ? ? ?28.9
4000? ? ? ? ?32.6
4500? ? ? ? ?36.0
5000? ? ? ? ?38.9
5500? ? ? ? ?41.3
5780? ? ? ? ?42.8

And finally, (while I was looking for those figures in the archives)....

Sorry to repeat this, but is still applies...When you call ACME, they're gonna primarily replace your current prop. This means that they assume their 13x12 5/8 prop is the quivalent to the stock prop. Kinda like us 1.26:1 guys that were told to replace 13x13 with 13x11.5 ACME. To that they might adjust a little based on your stated preferences regarding ballast or skiing, etc.

My first step will be to say, "my WOT throttle RPM is 5800, so the current 13x13 4-blade OJ Stainless is a little tall to start with." Let's say that 200 rpm equals 1/2" of pitch, and that the prop specialized for all-around runabout stuff would become 13x12.5. I ask him which ACME prop would be the quivalent to the theoretical 13x12.5 OJ stainless 4-blade. He tells me "that's the ACME XXX, a 13x11.5 three-blade."

To this, I ask for like 500 rpm (or more, just a guess right now) to improve hole shot with weight and improve throttle response at 22 mph. He says, "alrighty then, you're now in for an ACME 3-blade 13x11." I put down the visa and go wait for the UPS guy.

That might change me from 5800 RPM and 43 MPH GPS to like 6000 RPM and 37 MPH GPS. Pretty heavy hit to top speed, but the extra 500 rpm at wakeboarding speed would probably make the thing into a different boat.

There's an article in the latest WBM that talks about propping your boat and that just because you have Perfect Pass, there are still benefits to downshifting your prop. Besides quicker time to plane and better speed control, they claimed that thequick hole shot will end up saving you gas. I've always wondered how the scale tips in the 'quicker hole shot vs. higher rpms all day' battle. The article did say thatt he higher rpms increase wear on the drivetrain.

So that about sums it up ;-) Go get a GPS, spend some quality time on the lake by yourself, no ballast and a full tank of fuel and carefully plot your speeds. I'd do three columns: RPM at 500-rpm intervals between 2000 and WOT whatever that is. Record both indicated speed and GPS. To get the <2500 rpm readings, come up on plane and then back down. I'd also get a data reading at 22 MPH (RPM and indicated speed at 25 GPS).

Anyhoo, when you get back with ACME, you'll have two important figures: WOT speed and RPM & wakeboarding speed and RPM. Plus, hopefully you'll have read the markings (or better yet, taken a pic of them) and know the current prop mfr and part number, blade count, diameter, pitch, shaft diameter.

The thing about correcting for altitude is how much you want to optimize for your home lake's elevation. Just know that if you dial in for 4000 feet and then go to sea level, you'll be turning higher RPM. Just be aware of it. Heck, you'll have a spare prop that's already pitched for sea level!

[extruop]

Here are my prop numbers.

X-22  Half Tank of Gas.

Ballast Empty  Three people in the boat.

MPH numbers from Perfect Pass Paddlewheel.

[extruop]

I talked to ACME.  I gave them the info and they are recomending a 13 X 11.5 with a .080 cup.  It is a three blade prop.  Their model number 543.

I told him that although I do most of my boating around Salt Lake.  I also make several trips a year to Lake Mead and Powell (Quiet a bit lower in elevation).  I mostly wakeboard, I have quite a bit of ballast, but I still like to ski and dont want to sacrifice the top end to severly.

Oh ya, I forgot.  The ratio on my tranny is 1.26 (direct drive).

BTW- Before I pull the final trigger.  Any advantages to a left hand vs. a right hand prop?  Mine is right hand right now but I hear left handers are easier to drive.  Is it hard to switch?  What about the threads for the bolt on the prop?

[extruop]

Sheaht, its really a nut not a bolt.  Freak, you know what I mean don't you?

[toyotafreak]

Hate to go off of memory, but I'm pretty sure mine's LH. The nice thing about the LH is that I approach a dock at a bit of an angle, with the dock on my side. I coast in there and then when close, I drop it into reverse. This both slows the boat and begins to pull the ass end towards the right, sucking the boat up square to the dock - every once in a while I'll get it perfect and will be able to just reach over the window and grab the dock rail.

Seem to remember that Capt. Rick said that it's super easy to change the rotation.

[extruop]

The guy here at the old Toyota dealer (Marine Products) told me that the early production years (98,99) epics had right hand props.  Then in 2000 they switched everything over to left hand.  I asked him why, and he launched into a ten-minute diatribe about the politics of inboard towboats.  He said a lot.  But, in a nutshell claimed that Correct Craft runs right hand.  For so many years they were the gold standard for inboards so why not copy them.  Master Craft and everybody else runs left handers for the same docking reasons you just mentioned above.  Toyota switched everything over in 2000.

I talked to ACME.  He was confused about my WOT listed above (maxed out about 5000).  When I told him I had an aftermarket perfect pass he told me to check out the linkage and make sure I am really wide open at full throttle.

No surprise, when I got online today and checked the archives, Cyclone has weighed in on this issue.  I will fiddle with it next time I get on the water.

ACME still thinks the three blade 13 X 11.5 .080 cup is the prop for all around performance.  Based on the posts from the people who have switched to it, he is probably right.  Everybody who has bought that prop raves about it.  I still want to see what my WOT RPM is but I have ants in my pants and want a new prop for all the ballast I am running.  I will post when I make a final decision.

Thanks for the help.

[extruop]

Ignore that top table.  The MPH figures were with my perfect pass before I calibrated it with the GPS.  This table should be right on the money.  The gas tank was full and I had three people on board.  The water was not too choppy but a little rough.

[extruop]

Oops.  Forgot to attatch the table.  Here it is.