Hello im new here. Recently bought a 88 liberator 261with with a single 460. Motor has a holley carb and edlebrock intake. I believe it has the wrong prop on it. Its a 15x17. It gets on plane real quick but revs out at 4900. No gps in the boat yet but phone gps is saying around 40mph. I did some searches but couldn't find anything specific. Im thinking around a 21 pitch. Any help on this or where I could find help would be appreciated. Thanks!

If that prop is a 15" diameter and 17" pitch then it's unlikely that the boat will pull a 21". Maybe try a 19". Stick with a 3 blade on that boat it will be faster then a 4.

if its only pulling a 17 to 4900, I would want to know why.

I spoke with a few others and a 19 or 20 seems to be what I need to try.

if you have a cobra drive i have done alot of prop testing on a 211, same power but more hp then stock power..the boat loved a mach 1 4 blade the most..the prop we ended up with was a 16x20 and would top out in the high 60's..its just a heavy boat..