MIKEHTMSR24

with XR sportmasters and 525s 2005 model yr

throttleup

It depends on your set-up. What kind of props are you running now and at what speed and rpm? What gear ratio?

MIKEHTMSR24

This is a new boat that is in the process of being ordered. Just wandering what have other owners or prop shops used with this boat with XRs, Imco boxes, Merc speedmater lowers(2" I believe?), and stock 525s. I'm sure it will have at least 1.35 gears but not sure.
This is a buddy of mine that sold his old cat and is getting this 36.
Like everbody else we all want top speed but we all know that 99% of the time we are in cruise mode so mid range is really more important. This will not be a race style setup.
Will he maintain his top end and increase his mid range eff. by going with one of the new 5 blades and if so what are the numbers???

throttleup

If the propshaft is 1" above the hull then a 5 blade prop will work very well. The 6 blade props also perform exceptionally well on these applications.

I would expect that a 31 pitch 6 blade or 32 5 blade would be right for the boat if it is equipped with 1.36 gears.

Matt

MIKEHTMSR24

thanks for the info but need more
Will he loose some top end? What kind of percent, if any, increase will he see in the mid range on slip?
You said 1.36 I said 1.35. Not trying to be anal but isn't the XRs 1.34XX (which rounds off to 1.35) gears and the old Bravos 1.36?
thanks again for the time and info, it's nice to have some were to go for ???s

throttleup

Lost top end compared to what? Increase in slip compared to what?

A propshaft 1" above the hull is typical for many cats. You can go higher or lower and if you have the time and spacers it would be wise to do so to maximize the performance of the boat.

Matt

MIKEHTMSR24

If the boat is set up so that the engines are never hitting the rev limiters even with the lightest load using labbed Bravo 1s. Then how well will the boat do with 5s at top and mid range.
I know this is a little or a lot of unknowns on your behalf and understand it's hard to answer question correctly when you don't have all of the pieces to the puzzle.
When drive height is the the same between 4s and 5s then how do they compare?
Then throw the curve ball in and raise the X so high that the 4s will not work but the 5s will. Then how do the 5s compare at the higher X compared to the 4s at the lower X?

throttleup

The cats respond very well to 5 and 6 blade props. Cats are rough on props, especially the Bravo 1's because they have only 4 blades. I would expect the same or better top end speed with 5 or 6 blade props compared to the Bravo 1's. The boat will be much more pleasurable to drive with the 5 or 6 blade props across the board.

Of course if you were to take the time and fine tune the set-up of the boat then a 5 or 6 blade prop would perform at drive heights where the 4 blade wouldn't even be able to get on plane. The top end would be better than the 4 blade prop at a lower drive height.

It takes time to get the boat just right. The factory just doesn't have the time to dial every boat in. Not to mention that every boat owner and driver like a boat set-up a little different than another owner would with the same boat. So what works for one may not work for another.

Matt