JasonSmith

I'm thinking of removing my Whipples. I run really great slip numbers right now (9%, 93mph @ 5250rpm on a 1.34 gear) so I don't want to start over on propellers again. Would you switch from the 1.34/36 gears to a 1.50 or 1.65? Where is the formula to figure out what i'm trying to figure out?

Vinny P

( (pitch X rpm) / ratio) / 1056 = theoretical speed .... then allow for slip #'s

JasonSmith

guess what I'm wondering is what is the hp reduction to gear ratio increase to spin the same pitch propellers I was with the big power.

Mbam

How much speed do you think you will lose? 10 MPH?

Plug in the numbers here:
http://go-fast.com/prop_slip.htm

jeffswav

Jason, this website is pretty cool. Be sure to check out my threads on my speed results from raising the drive. I would like to have your input. www.rbbi.com/folders/prop/propcalc.htm

JasonSmith

I've used the BAM knowledge base extensively for years now.
Jeff, your "experiment" worked out well, just like we said it would. Bragging on myself, you hit right where I said you would, didn't ya?

jeffswav

Yep, you guys were right about the setup. Thanks for the good advice.