Prop experts challenge
 

39 foot cat
12,000 lbs
Running small pulleys 850-900 HP
Arneson 8's set up for Merc SM #6 props
Ratio 1 to 1:32

What would be the expert's calculation for pitch and diameter for a set of:

4 blades

5 blades

clueless
 

I have no idea.
but you could try using a prop calculator and see what you get, Mercurys site has one.good luck,sorry we could not help.

There are a few members here that would probably have a idea and are not even prop experts.:D

Expresscat39,

Do you have dyno runs on the motors?

What is the peak torque rpm and peak HP rpm?

Based on the numbers you gave above I would expect a top speed of about 110. I need to know what rpm the motors will run at WOT to give you a recommendation on a prop.

Matt

why does it seem impossible to find prices and info on Props for #6 drives? Both 4 and 5 seems hard to find out anything about

The #6 drives are becoming more popular. We deal with more and more of them all the time. We work with a number of race boats and high horsepower personal boats with #6 drives so we have experience with them. If you have any questions about a specific application please give us a call.

There are a few more variables with the #6 drive props than there are with Bravo drive props that have to be taken into account. The price of the props for the #6 drives is more than the price for the Bravo drives.

If you are interested in prices for #6 drives give us a call and we can help you out.

Matt

Dyno'd
 

We have the curves.

900+ lbs torque @ 6000 RPM.