Power Slot "Type" of Mod

[WakeGirl]

Have you been around the 25'? I finally got to see one last year at Oroville & then at the boat show where I got to get in & poke my head around. That thing is a friggin' yacht! I mean it was huge, the freeboard on it was incredible.

[VinRLX]

I wish I had a picture of the one I was in at the March boat show. It was amazing--not at all for me--but amazing nonetheless.

Oh Peter. . .any pics to share with us from that show?

[whiteVLX]

Have you been around the 25'?  I finally got to see one last year at Oroville & then at the boat show where I got to get in & poke my head around.  That thing is a friggin' yacht! I mean it was huge, the freeboard on it was incredible.

<{POST_SNAPBACK}>

They are friggin ridiculous in size when you compare them to a sportster. I've seen a couple roll through the local dealer and they are definitely a sight.

[UWSkier]

One reason the V drives are fast is weight distribution. They have the heaviest part in the back. Bad for holeshot, good for top speed. Having the motor aft gets more hull out of the water.

[SacRiverRat]

I'd like to have the first WSLSV to do 65!

Edited April 17, 2005 by SacRiverRat

[UWSkier]

I wonder how fast my bud's Response would go with the 17.5" prop from the VLX on it... We need an emoticon of a smilie scratching his chin in ponderous thought.

[SacRiverRat]

Yea - but I wouldn't want to sacrafice hole shot.. I get frustrated (being a speed freek) with the heavy feeling the boat has when boarding fully loaded.

Just need more power! [nice Tim Allen grunt in the background] Though have a big HP car, I know that even though it seems easy to just bolt on a blower or something - the reliablity suffers big time. No to mention the can of worms opened when pursuing a speed goal..

I'll just enjoy my boat - sigh - though I do enjoy the speed

And I like the contimplative smilie idea - maybe we need to have a forum to give Tracie more stuff to do, like expanding our smilie collection

[whiteVLX]

SOT, I've looked for smilies, but they're hard to find in the right size. I guess I could download one and look but it's easier to ask, what size are these Tracie?

[WakeGirl]

I'm not sure to be honest. I found a lot of them on Invision's client forums (that's the board software that we're using btw), there's a really long request thread for smilies there & if they have time people will just make them. Others I Googled for, the thing to look for is the IPB style. Heck, I've got Animation Shop, I could probably modify some, if I had time that is.

[JohnDoe]

The powerslot most definitely affects top speed. lets say it's 1.5:1. Thats reducing the efficiency by 50%! Thus, an engine that is capable of turning x rpms and then gets reduced by 1.5 turns physically cannot go as fast as as a malibu without the reduction. You may be thinking of CC's hulls, they are slow, but MC hulls are very fast, but the props are limited in revolutions as opposed to malibu's 5000-5500. What makes MC hulls fast are the number of reverse chines underneath (4 vs malibu's 2). Thats why a sportstar, with essentially the same hull as a prostar will run faster with a smaller motor becasue there's no reduction. I would never buy a reduced boat, it's just not near fast enough. I have a friend thats a former national champion and he skis at 46. No MC can come close, the 209 in WS mags test had the MCX and ran 43 with no barefooter! At least the lxi got 46. That'd be even better with the hammerhead. The MC wake is awful, but they are out of the running right off the bat because they're not fast enough. Rlx with the HH is guaranteed to run 51, some 53. Change the prop out on a slxi and it would smoke a 209.

[BillFooter]

A pick up truck in first and a Ferrari have nothing to do with hydrodynamics. Prop slippage is what makes a propellor efficient. The gear reduction allows the use of a higher pitch prop which will have less slippage and be more efficient. The MC hull is why the boat is slow. It is a very wet hull with high hydro drag.

Bill

[JohnDoe]

Well if thats true, then why did mastercraft have such low pitched props on their test boats.

I just disagree about the hull. I have been in prostars without the slot and they run high 40s. Thats also why Keith St. Onge's boat does not have the reduction (from what I have heard)

[JohnDoe]

By the way, I like your boat Bill. I love seeing newer closed bows. They are truly rare.

[WakeGirl]

Gear reduction is all about putting torque into the water, and getting the boat to "hook up", in car talk.

By gearing the tranny down 1.5:1, you are essentially driving the car in 2nd gear instead of 4th gear.  It has lots more torque by the fact that it's geared down.  Naturally with the same size tires (prop in our case), the power will just smoke 'em.  So, you need to go up in prop size to harness the power.  But, you haven't lessened the power, you've just harnessed it.....allowing it to hook up right NOW.  :) :)

Power is pointless.  Torque is all we need.

pb.

The math on paper only accounts for power and speed.  The drag induced during use, and the percent of change between tranny and prop size respectively, is the true answer.

A farmer's son (like myself) at Malibu installed a 1.5:1 in a Response.  It flew.  He wanted to use it.  Bob Alkema said no.  End of story.

Non-Diamond hulls are faster than diamond hulls.

A properly equipped 21 LSV is FAST.  Fast of the hole, Fast top end.  It will stay with a Response.  End of story.

pb.

Gear reduction lets you spin the prop fewer times over the same distance travelled.  Fewer revolutions = less slip = greater efficiency from a hydrodynamic standpoint.  Remember, we're not dealing with a solid here.  If we were, the argument that you can simply change a prop to overcome the gearing difference would hold water (no pun intended). 

OK I think I can explain why gear reduction works using automotive terms which hopefully everyone will understand.  If you have a drag car and a limited budget you can run smaller diameter drive tires to increase your torque and hole shot times, but it reduces your top speed. (basically what a 1:1 tranny is doing because no comp boat is geared for top end anyway)  If you want to go even faster with the same car you reduce your gear ratio in the drive differential and put bigger tires on that have more traction.  This keeps your overall gear ratio the same as small tires and stock tranny, but allows for more traction and the same top end.  You are able to harness your power more efficiently on the bottom with out losing the top end capabilities.  I think this is the same with a boat, find a way to get more hole shot without losing top end.

Joe

Another reason gear drives are more efficient is "effective pitch."  The propshaft angle on these boats is inherently inefficient.  For greater efficiency, the prop shaft should run parallel to the surface of the water.  There's a certain amount of "inefficiency" introduced with each prop rotation in this configuration.  If you can reduce the number of revolutions, you can reduce some of the inefficiency.  This is probably why the farmer's son in Peter's post saw such great performance out of his Response redux.

As far as Nautiques go, they're under-propped overweight tanks with extremely inefficient hulls.

the other difference is that a 14" prop has more surface area than a 13" prop, so it will have better "traction"/less slip.  This is why a 4 blade will have a better holeshot than an equivalent 3 blade.

Don't make me go into the "prop column"

If that comment doesn't get Rutat out of hiding, nothing will.

All of those posts, in addition to Bill's should explain why the redux is a great thing.

As far as the MC goes.... Every last person that I've spoken with that knows anything at all about the Big 3 will say that MC hull design is to blame for being slower, you being the first that I've ever come across that says no to that. On MBO you claimed it was the engine that caused MC to be slower (which you did agree with at the time), now you're saying it's the tranny? It's the hull design, always has been.

[stewart]

Just swap out that Hammerhead for a 383. You'll be satisfied then

[whiteVLX]

I ain't worrying one bit myself, alway got the reduction built right into the Vdrive.

[WakeGirl]

I ain't worrying one bit myself, alway got the reduction built right into the Vdrive. 

Awww, you had to go & rub it in didn't you? As for the HH, the only way that we'll be getting the stroker is if we either get a new boat (aint happening anytime soon) or the HH that's in there blows up inside of the next 200 hours. Seriously though, the next boat we get will have gear reduction & if we decide to keep this one well past the 300 hour mark we may very well put one in it.

[BillFooter]

MC uses quite a bit of hook in the hull at the rear of the bottom. That drives the nose down The faster you go the more it drives the nose down. The MC DD are not fast boats. MC is more intereseted in slalom wake than speed. You will not find many footers that want 44 mph or faster using a MC DD. They just won't go that fast. If you are talking about a V drive I would agree they probably have some that will run upper 40's. Nautique DD's are even slower on top end than MC. I am not saying that low top speed end is necessarily always bad. It just is for barefooting. (at least for me)

Bill

[Sunset_Bob]

This sounds familiar to me. Billfooter and myself have a buddy who spent alot of money to make HP in a Supra for speed. Guess what? It didn't go any faster. But it got to 43 mph really fast!!!

Faster it went, the harder it pushed the nose down. Same as the MC hull.

Bob

[JohnDoe]

MC uses quite a bit of hook in the hull at the rear of the bottom.  That drives the nose down  The faster you go the more it drives the nose down.  The MC DD are not fast boats.  MC is more intereseted in slalom wake than speed.  You will not find many footers that want 44 mph or faster using a MC DD.  They just won't go that fast.  If you are talking about a V drive I would agree they probably have some that will run upper 40's.  Nautique DD's are even slower on top end than MC.  I am not saying that low top speed end is necessarily always bad.  It just is for barefooting. (at least for me)

Bill

<{POST_SNAPBACK}>

OK, are you willing to argue that the Nautique hull is more efficient than the MC's? It's not. Between, spray relief pockets and yadda yadda yadda, it's a complete DRAG. But, nonetheless, it hit the 50mph mark in the tests. The diamond hull, as well as the SSP, does EXACTLY what you are talking about in terms of pressing the bow in the water. The reverse chines lift in the rear and push down in the front. So...malibu, 50mph (or higher), nautique (50mph), and MC 43. Whats the difference? powerslot, plain and simple. You're right that non one wants to use a MC to foot, but not just becasue of the wake, it's just not fast enough. Think about it. It is simply, not fast enough to pull anything but figure 8 tournaments. There's one reason that it's too slow...the powerslot. If you're in an aston martin in first gear, I can still outrun you in a corvette if I'm in second.

I'm curous when the last time you drove an MC was, the new ones that I ahve driven, when wide open, soudn like the motor is going to pop out of the boat and we're going 43! The older carbed MCs with basically the same hull, will run 47-50. I hit 50 in our Rlxi this weekend, same RPM as a new MC that does 43, one thing different...the powerslot. Does it rip you to 36, sure. Is it too slow for any highend footing? yep.

I GUARANTEE you that an MCX 197 will outrun any monsoon Rlxi in the world if it did not have the slot.

[JohnDoe]

Wow, I just reread your post. Nautiques DDs are slower than MC DDs? What?!!! Read the test, The 197 hit more than 50!

[JohnDoe]

Gear reduction is all about putting torque into the water, and getting the boat to "hook up", in car talk.

By gearing the tranny down 1.5:1, you are essentially driving the car in 2nd gear instead of 4th gear.  It has lots more torque by the fact that it's geared down.  Naturally with the same size tires (prop in our case), the power will just smoke 'em.  So, you need to go up in prop size to harness the power.  But, you haven't lessened the power, you've just harnessed it.....allowing it to hook up right NOW.  :) :)

Power is pointless.  Torque is all we need.

pb.

<{POST_SNAPBACK}>

The math on paper only accounts for power and speed.  The drag induced during use, and the percent of change between tranny and prop size respectively, is the true answer.

A farmer's son (like myself) at Malibu installed a 1.5:1 in a Response.  It flew.  He wanted to use it.  Bob Alkema said no.  End of story.

Non-Diamond hulls are faster than diamond hulls.

A properly equipped 21 LSV is FAST.  Fast of the hole, Fast top end.  It will stay with a Response.  End of story.

pb.

<{POST_SNAPBACK}>

Gear reduction lets you spin the prop fewer times over the same distance travelled.  Fewer revolutions = less slip = greater efficiency from a hydrodynamic standpoint.  Remember, we're not dealing with a solid here.  If we were, the argument that you can simply change a prop to overcome the gearing difference would hold water (no pun intended). 

<{POST_SNAPBACK}>

OK I think I can explain why gear reduction works using automotive terms which hopefully everyone will understand.  If you have a drag car and a limited budget you can run smaller diameter drive tires to increase your torque and hole shot times, but it reduces your top speed. (basically what a 1:1 tranny is doing because no comp boat is geared for top end anyway)  If you want to go even faster with the same car you reduce your gear ratio in the drive differential and put bigger tires on that have more traction.  This keeps your overall gear ratio the same as small tires and stock tranny, but allows for more traction and the same top end.  You are able to harness your power more efficiently on the bottom with out losing the top end capabilities.  I think this is the same with a boat, find a way to get more hole shot without losing top end.

Joe

<{POST_SNAPBACK}>

Another reason gear drives are more efficient is "effective pitch."  The propshaft angle on these boats is inherently inefficient.  For greater efficiency, the prop shaft should run parallel to the surface of the water.  There's a certain amount of "inefficiency" introduced with each prop rotation in this configuration.  If you can reduce the number of revolutions, you can reduce some of the inefficiency.  This is probably why the farmer's son in Peter's post saw such great performance out of his Response redux.

As far as Nautiques go, they're under-propped overweight tanks with extremely inefficient hulls.

<{POST_SNAPBACK}>

the other difference is that a 14" prop has more surface area than a 13" prop, so it will have better "traction"/less slip.  This is why a 4 blade will have a better holeshot than an equivalent 3 blade.

Don't make me go into the "prop column"

If that comment doesn't get Rutat out of hiding, nothing will.  

<{POST_SNAPBACK}>

All of those posts, in addition to Bill's should explain why the redux is a great thing.

As far as the MC goes.... Every last person that I've spoken with that knows anything at all about the Big 3 will say that MC hull design is to blame for being slower, you being the first that I've ever come across that says no to that. On MBO you claimed it was the engine that caused MC to be slower (which you did agree with at the time), now you're saying it's the tranny? It's the hull design, always has been.

<{POST_SNAPBACK}>

It is the motors when they are underpowered next to a malibu. They do not have congruent motors. So, when people say the MCX or LQ9 is slower than a hammerhead, or course, it's the motor. There's 50 and 20? hp difference.

Anyone who has looked at the hull of a MC recently, can you please tell me where the arguement is coming that they are slow hulls? I mean, tige literally has a lip at the hull base, and yet it still outruns MCs!

If MC hulls have so much drag and are so slow, then why do they smoke malibu's (out of the hole) ? The Slot. Why do malibu's fly by them, the slot!

It might seem likeI'm knocking the slot, I'm just saying that it's too slow for a lot of people out there. Even though a lot of 'footer haven't been sold, a Rlx with monsoon (or more) is the only thing that even fits what a footer would be looking for! No MC goes fast enough, CC's wake might as well be a jet ski, so that leaves bu.

Edited May 10, 2005 by wakebrdgod

[JohnDoe]

A pick up truck in first and a Ferrari have nothing to do with hydrodynamics.  Prop slippage is what makes a propellor efficient.  The gear reduction allows the use of a higher pitch prop which will have less slippage and be more efficient.  The MC hull is why the boat is slow.  It is a very wet hull with high hydro drag.

Bill

<{POST_SNAPBACK}>

Drag has some, but not everything to do with it. We had a barefoot nautique with a 454. Have you ever seen one of those? The V is so deep we could ahve taken it to Tahiti and back. It without a doubt had more wet hull than a MC 230. But, it would run 50 with 5 people in the boat and probably had about 300 ps horsepower. Drag, in real life, is not near as big of a deal as pure revolutions. In fact, soem theorize that more wet hull, makes faster boats (to some degree). Given that MC have a very light feel to them, I might agree.

[WakeGirl]

If you're referring to the 197 in Waterskimag's test @ 43mph, please show me where that boat has a Powerslot. It doesn't mention it, & the prop size would indicate that it's a 1:1 tranny in that boat.

[JohnDoe]

Well, you're right that nothing in that test mentions it, nor does any other MC test, nor does MCs website. The 190 went less than 43, the 197 went 43 (with the MCX) and the 209 did 43 with the MCX. My monsoon runs 50 with a 4 blade, with less horsepower than the MCX, and even waterski calls the MC hull drag-less. So, a 42 mph 190 makes perfect sense because it has the little motor. Slow nonetheless, and while I think that there is a chance that it has the powerslot, I have no proof. All MCXs (to my understanding) come with the slot. So, by bumping up 40 horsepower, you pick up 1 mph of top end, which is still significantly slower than a lesser-powered monsoon. The nautique has 25 more horses, but outruns it by 7 with practically a tractor tire for a hull. hmmmmm...

Ok, look, while I think that the slot is bad, I'm not saying that some people won't or shouldn't like it. I got involved in this because a barefooter on another thread was looking for a boat. Whatever the case, a boat with 350 hp should go 50 in DD ski boat.

Someone said a while back that their Vdrive served as their reduction. Just to clear the air, thats not accurate. There is no reduction in Vdrives or ANY of Malibu's boats. Actually, there is no reduction in anyone's boats but MC, correct me if I'm wrong.