Michigan Wheel Vortex not quite like Mercury Alpha 4, suggestions?

[gt2003]

I had just gotten up on slalom behind my 2007 Tahoe Q6 with the 4.3L MPI motor the same day I hit a low spot in the lake and wasted my Alpha 4, 14x20 prop. I looked around and saw the Michigan Wheel Vortex props and had a couple of people tell me they were the same as the Alpha 4. That wasn't my experience today. On my gauges, and a little off from what I was told, the Alpha 4 would get me around 43-344mph at about 4300 RPM. I know this isn't 100% correct as you all have taught me about slippage. But, the Vortex today was running 47 mph at 4700 RPM's (not exact, I know, just an example). Also, the dang prop couldn't pull me out of the water. I would be right on the verge of my slalom ski topping out on the water and the boat just didn't have what it needed. Any suggestions? The prop that came with the boat is an aluminum 14x21 and the Alpha 4 I got up on is a 14x20. I just need the extra torque/hole shot to pull my big butt out of the water. I'd like to keep things aluminum for now. Does the Alpha 4 come in a 14x19??

 

[SkiDad]

no, but you could try the 18 pitch alpha 4 and just keep an eye on your tach - you might go slightly over. Or look at the Mercury Spitfire (that is available in 19)

I run a low15 pitch on my boat even though i can get up fine on a 17 but i like getting up as fast as possible so I have more energy for the run - obviously my boat numbers are not comparable b/c I'm an outboard but same idea.

 

[gt2003]

The Vortex actually is VERY SMOOTH just cruising around and it kicks the RPM's up where they are supposed to be at WOT where the 3 blade 21pitch that came on the boat and the 14x20 Alpha 4 struggled to keep RPMs even at WOT at 4300-3500. I just ordered the 14.5x18 Alpha 4. I'm sure it will do the trick. I'm not worried too much about WOT as I don't spend much time there but I will definitely keep a close eye on it. Looking forward to next weekend already!

 

[SkiDad]

if the vortex is turning higher RPM, i wonder why it didn't pull harder ? was it a 4 blade or 3 blade ? do you think it was ventilating during take off or something ?

 

[gt2003]

I have no idea. It is a 4 blade 20 pitch just like the Mercury Alpha 4 that pulled me out of the water a couple of weeks ago with the exact same load as this weekend. It started off strong then would just kind of stall. Unfortunately I wasn't in the boat to see/hear/feel what it was doing so it's hard to answer. I wish I could give you better info.

 

[gt2003]

Something I just thought about. The Vortex is a "factory second". I assumed that was because of blemishes but maybe I'm wrong. However, the boots/bindings for my ski come in Wednesday and my new 14.5x18 Alpha 4 comes in Thursday. Can it really get any better?

Ay other ideas on why the Vortex seems so different from the Alpha 4?

 

[SkiDad]

it's just the blade design difference on the Vortex (i haven't tried one personally) - i have a Hustler prop that is the same pitch as my other 15 pitch props and b/c it is highly cupped and progressive pitch it is a little harder to get up. Sometimes a little slip off the bat is a good thing for slalom prop. The 18 will do the trick, trust me.

 

[gt2003]

It makes sense, just a little disheartening! I was up, out of the water and almost slaloming AGAIN for the 2nd time in 20 plus years. Oh well, the new prop will be here Thursday and I"m taking most of the day off on Friday to play. Good times ahead! Depending on how the new prop runs (RPM's, pulling etc.), I might start looking at a 17 pitch revolution 4 for next boating season! Wow, this boating stuff is fun, lol!

 

[gt2003]

The 14 1/2"x18 pitch Alpha 4 is installed and ready to go. I'll be on the water in less than 4 hours. We'll see how this goes!

 

[gt2003]

REDEEMED!!!!!!!!!! I changed to my new Alpha 4, 14.5x18 prop, threw on my new Obrien Synchro ski and was up in 4 tries! Yep, longer than I wanted but hey, I'll take it! Just a few more weekends to practice until this year. However, I'm pretty happy with the new prop!

 

[SkiDad]

love it !

so how do you like the Syncho ski - is that a 69" and how fast are you skiing it ? - I have a shaped Connelly ski in 67" but it really the surface area of a 69 b/c of the shape. It feels about right at 28 mph and I'm about 215 currently

 

[gt2003]

I do like the Synchro and yes, it's the 69". The double boot is a little different but not unbearable. Unfortunately I'm not sure how fast I was going. My gf was driving and is new to boat driving this year. She was more concentrated on the mirror and looking back at me to even notice. I made one "Ok" turn then accelerated as fast as I could outside the wake on a turn then I let go after riding just a short while. It seems stable going straight and it seems to cut well for the limited time I was on it. The hamstrings and forearms are taking a beating but at least I've been up a couple of times. Might go out again today, not sure then maybe once more next weekend. The year is coming to a close, much too fast.