Ivo hub

I am looking for a used but complete IVO Hub for a 3 blade airboat. I do not need any blades for it just the hub itself.

mev3rd,

Just one caution while shopping for your replacement IVO hub. You need to make sure that the bolt pattern is correct.

For example, some folks may mention that "It's a standard Rotax pattern". Well, I know of at least 3 different Rotax bolt patterns. :-o

I don't know what bolt pattern your original IVO prop hub was. I "assume" that it was a "standard Rotax bolt pattern", but that is a BIG "assumption".

It seems like most folks assume the 100 mm x 8 mm pattern to be the "standard Rotax bolt pattern", but believe me that there are other Rotax patterns out there. ;garfield;

It may even be something completely different. (There's some OTHER bolt patterns to chose from) ;bawl;

Contact IVO, take measurements, and determine what your original pattern was was before you buy anything...

You may find it cheaper in the long run to buy the replacement parts that you need directly from IVO.

You may even want to consider using a different prop altogether. But that's another subject...

Good luck with it. ;thumb;

Duane

http://miniairboatassoc.com/forum/at...6&d=1320506984 Thanks Duane. This is what I sent IVO. It is very hard to read I was hoping with it being their product they would quickly know by the numbers that can be read what it is that I need.

mev3rd,

Oooh... that looks REALLY rough. ;rasta;

Hopefully IVO can make some sense of it. I sure can't.

But you'll need to talk to them about the HUB.

Good luck.

Duane

mev3rd,

Here's MORE unsolicited advice, for the $0.02 that it's worth.... :roll:

What you have is a Direct Drive VW. Now, for that direct drive engine to be able to even begin to develop it's full HP potential, it's going to have to be able to run in the 5,000 RPM range. You can NOT safely do that with a 60" prop.

For your engine to develop it's full HP potential, as a Direct Drive, you'll need to stick with with a much shorter prop. A 3 bladed 42" Ultra prop comes to mind.

Think about it, and look into it.

Duane

Another member that has had a lot of experience with Direct drive on several different engines, including VW, is Papee. It might not hurt to run it by him!

Dave

IVO replied back they have not made the model prop that I have for several years, They also no longer make any replacement parts for the Hub. So it looks like I am going to need a new prop.

Back when I was in your shoes;rasta; I found the ultraprop to be a good choice. It's economical, and adjustable in diameter and pitch. I could perform a lot of experimenting in a short amount of time. In fact, I would probably still be running one but my rotax re-power likes a bigger dia prop.

Bruce

I have a Ultra Prop here if you want to try it, you'll have to get bolts for it though. I may consider selling it if you like it since I'm going with Chucks new setup in the spring. I'm not sure what length it cut at, I think 55". I have a few different pitch blocks for it also. The way it is set up now was for my 084 and turned 3000 rpms. I'm pretty sure the Ultra Prop is good at 3100 rpms up to 59", I'll have to check on that. I'm sure at the length it is with other pitch blocks in it, it will slow your motor down to the needed rpm. I would be very interested to see what a VW motor will turn it like it is now compared to the 084. It has a couple nicks in it from where a lure went through it first time I took it out but nothing big enough to affect the prop.


I like the shorter prop length for these props, it's more like a power prop. It gets out of the water quick with the shorter length but the top speed isn't as high as my other prop, a wider stick prop.

mev3rd,

Honestly, I had my my fingers crossed that you'd figure out how to get that IVO prop working. I wouldn't have bet money on it, but I did have my fingers crossed for 'ya. ;thumb;

I really don't know if an UltraProp will be the right alternative, but they are fairly inexpensive to experiment with. ;garfield;

However, I do stand by what I've said before. A VW engine will need to reach somewhere in the high 4,000 to low 5,000 RPM range to develop it's full HP potential. I don't know what RPM the old VW engines needed to reach rated HP, but 5,400 is what I seem to remember. I could very well be wrong. :-o

No, you should not need it to run at full RPM or HP most of the time. But, I'd think that you'd want that ability when you do need, or want it.

You are now in the prop shopping market. Take your time, do the research, and buy the right prop the first time. It'll save you time and money.

Good luck with it, and please keep us all up-dated.

Duane

A relatively stock motor would be good direct drive. They are made to run about 3400 rpm, any more would reduce their reliability. IMHO unless you are going to build the motor for more rpm I'd stick with direct drive. It's not going to be a speed demon though. If it's putting out the rated HP @ 45 or so a 52" wood prop or the Ultra prop should get you at about 30 MPH.

mev3rd,

I have an inquiring mind, so I had to look into it some more. :&&:

It was a little difficult to find HP at RPM specs for boxer type VW engines, but I eventually did find a couple.

For example:

The 1966 1300 cc engine was rated 50 HP at 4,600 RPM. And 67 ft lb torque at 2,600 RPM.

The 1967 1500 cc engine was rated 54 HP at 4,200 RPM. And 77 ft lb torque at 2,600 RPM.

So they don't have to run at 5,400 RPM to reach max HP, like I thought. I admit it, I was wrong. :eek:

Interestingly, they both show peak torque numbers at 2,600 RPM. Hmm...

So, I looked some more... and it got me to thinking...

There are companies that SPECIALIZE in VW based aircraft engines. DUH ! ;garfield;

Those would be the folks for you to put your questions to.

Here's one that looks promising:

http://www.greatplainsas.com/ 402-493-6507 info@gpasc.com

They sell parts, kits, and turn key engines, for both pulley end and flywheel end direct drive applications, as well as reduction drives.

I bet they could answer more questions in one phone call than we ever could.

Duane

My info was based on how they were designed to run on the road. Having a few VWs in my day that were run on the road, 2 vans and a bug, I know their traits. With the stock gearing and tires they will run down the road at aprox 3400 rpm at 65 mph. Having one I know I wouldn't have wanted to push it much past that for any length of time. Now the motor on my new race buggy is a different beast, it likes the rpm.

The aircraft type motors either with reduction drives or flywheel drive are heavily modified. A lot of work goes into the block itself to allow it to turn more rpms reliably. They also use dual bypass cases and specialized crankshafts, rods, heads, etc. You can easily get $3000 in the mods to make this happen and end up with over 2000cc and around 80 hp. Comparing apples to apples though I still think the relatively stock motor is best suited for the direct drive application. With my new endeavor and site I've been doing a lot of research for the new site. I've been researching all the specs for different motors and engine classes. Hopefully before long I will have all the charts on the Tubebuggies.com site. For some reason my real work gets in the way of my fun.

I like the way my 084 is set up direct drive, I turn my prop at 3100 rpm normally and can turn it to 3600 if needed for short bursts to get out of trouble. OR into it as the case may be. :oops: The prop and pitch is tuned to the motor, keeping the motor within the rpm range both the motor and prop can be most efficient and reliable. This also has a lot to do with the hull itself and the weight of the boat. You must think ahead and decide what you want, if you want to to haul more weight or add accessories to your boat running a lower hp motor may not be your best choice.

A good example of this is a boat I saw at the ramp this past year. It was a very nice build, aluminum hull and nice fresh stock VW motor running an Ivo prop. It was a beautiful boat but... He had all the fancy on it, fold up instrument panel, enclosed electrical panel, tool box, nice trolling motor, as well as other accessories. The problem is, it would not get on plane. Each setup has it's limits, if you want to do more it's time to move up.

As in reference to the OPs boat, it should do well on that hull with a fresh motor on it and the right prop.

http://tubebuggies.com/images/front4.jpg

Hey mev3rd, you are only a few miles from my shop, Airboat Pro's. Stop by and let me see your project. Maybe i can help.
Thanks, Chuck

Papee,

I've only had 2 VW automobiles. And that was a very long time ago. Neither had a tach as I remember. (actually, the dune buggy had NO gauges at all) I do remember that they both sounded like they were screaming at road speed. ;garfield;

But now that I think about it some more, if you really pushed them, you could get to "about" 85 MPH. So 3,400 RPM at 60-65 MPH does sound about right. ;thumb;

mev3rd,

I did find one other thing that you may find of interest. Tennessee Propeller recommends a 52 x 26 prop for a 1600 engine, and a 52 x 28 prop for a 1800 engine. (both direct drive)

http://www.tn-prop.com/prop.htm

So, my earlier suggestion that you needed a 42 inch prop was way off. My mistake. I apologize. (again) :oops:

I seem to have developed a very bad case of foot in mouth disease lately. :eek: So, I'll just STFU.

But before I do, let me "suggest" that whatever diameter prop you go with, go with an adjustable pitch prop.

Yeah, they may cost a bit more up front, but you'll be able to get the pitch that you need, by buying just one prop.

Duane