Need to know your experience with propping a Fountain. I have a 1993 (no step) with 525SC.

I was running 80+ with Mach 14.5x28 4 blade with standard Bravo I.

Had to switch props because of new prop shaft diameter(XR drives) change. No hub was available for the Mach with larger prop shaft.

First attempt is a Hydromotive 15x27 4 blade. I've lost 7mph in midrange (3500)! I can't run WOT yet due to drive breakin!

Can anybody share their setup and results on a non-step 35' with similar (more-or-less power) setup? I am trying to find the right prop with the minimum number of exchanges with Hydromotive.

Any help would be appreciated.

What are you using to check your speed? GPS or speedo. We ran both Bravo 1's and Hydromotives on our 35 twinstep. Had either set of props been worked? The Hydromotives do slip alittle more in the midrange than a Bravo 1 dont know about the Mach's. 1/2 inch less in diameter and 1 inch less pitch may may turn less mph at the same rpm, but I dont think it would be 7 mph. Their are some other things to look at, do the Hydromotives or the Mach have flare rings? If one does and the other doesnt beside the difference in pitch and diameter that will effect how they perform at a given rpm. Our twin step 2000 had 29 pitch Hydromotive 4 blades, we ran 500 HP EFI's also ran 30 pitch Bravo 1's The Hydromotives were faster on the top end the Bravos got on plane easier and cruised at a lower rpm at the same mph. Hope this helped. Oh by the way I just happen to have a set of 28 Q4 Hydromotives for big propshafts. I would make you a deal on.

The most important number is the WOT rpm. The Hydromotive Quad IV will have a slower cruise speed, like beak boater stated. That's due to blade area and blade design. Like beak boater also stated the Quad IV is generally faster on the top end.

It really comes down to what kind of boating you do and what's important to you. If top end speed is the goal the Quad IV is probably going to be the fastest. If you want a fantastic cruise speed with a top end about the same as a Bravo 1 then the Hydromotive P5X is an outstanding option. A Bravo 1 would put you mid way between the P5X and Quad IV as far as cruise speed goes.

Matt