Just finishing putting Whipples on the 525's of my 03 42 Fountain Lightning. Still have the stock XR outdrives. With the 525s, 1.5 ratio, 30 pitch 4 blade B1s, I could only reach 78 mph at Lake Powell (3600 ft) turning 5100 rpm. My slip calculations are in the 25 % range. Now with the 700+ HP, where do I go with the prop set-up? Any direction/suggestion is greatly appreciated.

1.36 gears would be a good start

Get some 5 blades from BBlades in the mid 30's for testing.
Carder

oops, they are 1.36--had 1.5 on the 27 fever ( you know, 120 -121, whatever it takes!). You suggest BBlades will be most helpful? Sounds terrific---I'll call and see if I can demo something; I'm thinking 30 pitch maximus 5 blade, then I'll work my way up from there. Thanks !

I added 100 hp per engine last year and went from 28p 4 blades to 31p 5 blades (equivalent to 32p 4 blades)
If you have added nearly 200HP, your going to need a larger change, plus Brett probably has outfitted a similar boat, and knows where to start... It's a process, but it sure is fun!

Carder

Thanks for the help! I'll talk to Brett.