Originally posted by 25 Outlaw 502:
I don't know what drive ratio I have but I will have the service department check
Hey Larry,
Sounds like you're on top of the GPS & tach situation. I'm not a bettin' man (OK, maybe a little), but with those numbers, I would bet $1 that you have the tall gears in the drive. Perhaps they are avoiding the subject to keep from switching drives?
Some food for thought- if you can get your 1.5 ratio drive to spin these numbers:
5,000RPMs w/23" prop @ 11% slip = 65MPH
4,800RPMs w/25" prop @ 11% slip = 67MPH
Lab finish will remove a little slip and maybe give you a few more RPMs, but the rest is the motor, boat & setup. There's a prop speed/slip calculator at: http://boatpropellers.com/propcalc.html
Good luck, & let me know how it turns out! http://www.goldenplasma.f2s.com/foru...es/happy43.gif
Jeff