Repower 21

[McGillicuddy]

Originally Posted by pair of jacks

By the way- the top end speed I quoted of 31 kts. was with 85 gallons of fuel (out of 95 gal. capacity) and just me on the boat but with all my fishing gear/bags/etc.

AV plate is bone dry (above water) while on plane.

Your 85 galllons is a lot more weight than the 30 gallons used in the 2 motor tests on the Dusky 203 so comparing your rig to those is not very accurate, and obviously the hulls make it "apples to oranges." Bigshrimpin mentioned the Dusky is smaller than the SeaCraft. The specs had led me to believe it was a littler bigger, so throw my assumption is out the window.

Sounds like you're dialed in on motor height. 31 knots is nearly 36 mph.
I simply thought a 21 SeaCraft hull would out perform the Dusky on the top end.

I posted the 2 tests for capnkid to compare the 2 motors on similar hulls. The test were done 68 and 95 deg temps so that alone would make some maximum performance difference.

Your real world experience with the 21 and 175 etec motor are the best info capnkid could ask for. Your suggestion of a 200 etec makes good sense.

Regarding props - if you make the change, be careful with that bigger blade. I don't know the two props in question, but if you're currently at 5400 rpm, a bigger diameter might set you back.