When I want to run full out, my boat wants to porpoise unless I trim it way down and of course the speed goes way down too. Does cupping a prop fix porpoising?
When I want to run full out, my boat wants to porpoise unless I trim it way down and of course the speed goes way down too. Does cupping a prop fix porpoising?
What Boat?
What Motor?
What is the current prop?
What are the WOT RPM's?
might not be the prop. my Crestliner PT18 would porpoise really bad. raised and lowered the motor, tried different props, no difference. put four wedges and it helped a little. four more wedges and I can at least run the boat but no speed and still can't trim enough. Crestliner is letting me use the boat til the season is over, then building me a 2018 boat. I guess they screwed up in testing this model as just about all of them are going back.
I just switched from a four blade to a 3 on my Sabre and discovered Porpoising also.
21 Lund 1775 Impact XS 21 Merc 115 Pro XS
I looked at a vt 18 today and it has trim tabs. do your boats have the welded trim tabs ? will be running a Mercury 155 XS
Put a foil on the cavitation plate and it should solve your problem. There are a few BBC members that make some really nice ones!
Just can't leave well enough alone!!
98 Stratos 273 w/ 150 Faststrike
Chris Bailey makes a nice one .
Have the prop checked by a good prop guy. If it's porpoising that means the prop won't carry the bow and sometimes you can add cupping to the prop to help it carry the load but it depends on what boat and prop you have.