Strange Prop Question: 30ft Cat Outboards
 

I have the old Hooter triple engine 30ft Cat that was re-rigged with Twin 2.5 osr engines. The previous owner said he always had to run 4 Blade props to get extra transom lift because the boat was a little heavy in the back from the extra beef for the triples.

So I was running 15 x 26 Worked 4 Blades for class 4 comp. (85mph max). worked pretty good.

Well I tried a set of 25p 4 Blade Hydromotives and the boat worked much better, It had more transom lift, More top speed & more acceleration.

Is this normal for a Hydromotive to work better of a O/B Cat? I'll stick with them or maybe find some 26p or 27p so I dont have to spin my motors to 8200rpm to get 85mph (class limit).