Prop suggestions Ol 37 GTX
 

Need advice regarding props for newly rigged Ol 37 GTX

engines are making 1000hp @ 6000rpm and 1000lbft @ 4400rpm
Arneson drives 1.32 gears

The props suggested now are 18x32x18R.

if anyone have a couple of props in that dimension and interested in selling please contact me.

as I looked over what’s listed it seems to be most 17” diameter props for sale, do anyone no if my hull would work with the smaller diameter or have any input as I can be completely wrong an the 18x32x18 props.

I want to bye used props to establish baseline.

I live in Sweden so the market for props are really limited.

grateful for all help I can get
Peter

Your set up is very unique and I haven't seen any other OL's with Arnesons. I think testing props is going to be the only way to get it dialed in.
You could try calling Outerlimits for advice.

Guessing props
 

It’s true, probably a lot of testing is the only way to the best props but I was hoping there are some guys that know the hull and had some input of what the boat wants.

The boat is new to me, never drove it. I bought it last spring from some guy in Danmark and the boat supposed to be in good drivable condition. I couldn’t go look at it in person do to the corona situation so I bought it on pics and videos.

But when I got it both engines where frozen end the blocks had cracked the intercoolers where cracked and so on...

Here I am one year later and doing a makeover looking forward to this summer so I can go boating.

After what I heard the boat has gone 120+ with xr sport masters on its and 1.26 gears with Maximus 15-5/8x34 and that’s how it was when I bought it.

grateful if someone has input or ideas on what the hull wants and recommendations on where to start.

thanks Peter

There were only a few 37 gtx’s built, but I’d imagine you could use a 37 stiletto with 6’s as a comparative starting point. I only know of one other ol with Arnesons and it’s an sl44 my buddy had built new. Completely different hull

So, where are all the Ol experts when you need the...?

No one has expertise in what your attempting to do. You’re the first to put those drives on that hull, so pave the way. Someone might have an educated guess if you post propshaft height and distance off the transom of the props.

Just thought that someone maybe would have some input from the stiletto with #6 drives.

I read somewhere in a thread here on oso that a stiletto with big power and #6, at the time belonging to “thundersone” (maybe misspelled) had some info that when going up from 17” 5 blade 15r to 17,5” 4 blade the boat felt loose and started to porpoise over 110 but when I got back to 17” 5 blade 15r all went away.

thanks
Peter

we run arnson8s on a slingshot 388 things to note are no bow lift or trim you lower the drives as the hull rises up with speed to keep the props the correct depth also big surfacing props has massive bite offplane so use much caution when shifting into reverse its possible to break the reverse plates you need really good trannys and large u joints that are changed often big blower engines are awesome but around the docks there is a bit of a learning curve to shift on the low point of the blower roll yet not stall it.... we shift and give it a jab of throttle to squirt a bit of fuel in works well

I have a beautiful set of Mercury Racing 17.5x32 5 Blades if you are interested.

What rake?

What is your prop spacing ? What I have found in my prop testing is 17in and smaller my boat does not like to get on plane with them and my boat responds well to high rake props . I run a set of 31 pitch 18 dia 20 rake

Do you mean the drive c-c?
Center distance is 22”

Yes center to center mine are 34in apart what drives do you have and what splines are on your shafts ?

Drives. Arneson ASD 7M HD, #6 spline.

I would think that with your set up the props you are looking for are close to what need , but you might be able to get away with a slightly smaller diameter if you need to get to your max RPM at neutral trim . My buddy always told me once you find the perfect set of props you will sleep with them under your pillow

Do you have SSM or arneson splines? I have pair of 16.5x34 and 17x33 arneson spline rollas in Finland. I’m interested to exchange to bigger diameter props.

#6 spline won’t work...

thanks anyway

I’m interested, what rake are they? How much do you want for them?

What boat do you have?

I have a non-step 35 fountain with 800hundreds and arneson ASD- 7 I also have 1:32 grears

https://cimg7.ibsrv.net/gimg/www.off...44b6fc0eea.jpg