i have a 1998 25 active thunder w/ hp500 it has a 12" stellings ext box bravo1, running a 26, 4 blade prop. when i get over 1/2
throttle the boat porposes the faster i go the more it porposes.
unless i have the k planes down ,but that slowes you down.
ive been told it may be the ext box. i have talked to many other 25 thunder owners they all say there boats run level but none have a ext box. what can i try :mad:

thanks 25 thunder

Try different props. Different style not pitch.

It's been said here on the board that a 3 blade Like a Mirage PLus will carry the bow more and a four blade will lift the transome more.

I agree with Tinkerboater

Dido! I went through this last year trying different props. Have been running a standard Mirage 3 blade and went to a Mirage Plus and had the porposing problem. Was so bad they we never could get much over 1/3 throttle.

Hope that helps?

Tab's at level with the bottom of the boat shoudn't slow you down, they will keep the boat from going as far back in the water when you come off a wave. Now if you have to go past level then it will slow you down. And the boat should be able to run with them up to. So like eveybody else play with the prop. Call Darin at Houston Prop.