Yes Thanks for the explanation, totally agree with the porpoise problem, and i can understand what you said.

I have 550SC on mine and still porpoising, I am looking to go 750's NA, do you think it will be enough to free her...?

Franck.

Mine propoises a lot between 50-low 60's until I hit 66mph (or 4400rpm's) and then she's good to go..but then so is my fuel gauge as a I watch it move..haha..problem is if you want to cruise at speeds in the 50's you tend to have to trim down the drives a lot or use some tab..

750's should get you through the hump...just keep in mind my previous post

hawk 600's (550 hp) would just get past the hump. mid to high 60's was bad porpoise, you had to run wide open (70-73) to get out of it. you will need a minimun of 600 hp to be happy with the ride in my opinion. this was also on a trs boat. hope that helps

Thanks for the information! that's what I wanted to know.

Is some of the porpoise problem caused by C.G. with bravo vs non bravo drive hulls ?
ed

I don't think so, because I have Konrad (and trannies) and still porpoising if not putting some tabs....

What about props, maybe some props tends to porpoise more than others...?

I would have to think so. There is an older thread that talks about the difference

http://www.offshoreonly.com/forums/c...-vs-bravo.html

Using the information stated earlier in the thread that you need 600+ HP to start to free up a flat GUN, I am sure a regular bravo drive wouldn't last long with that kind of horsepower. I think that if I find a bravo Gun that I like, that I should start saving for XR or bettter drives...or just buy a TRS boat and switch to Konrads..

That's interesting, so a bravo boat will porpoise worse than a TRS boat due to CG and both will porpoise due to small power in the back.
I think a good prop man could help some, maybe..I would be interested to know how Tank's Gun rode with 525sc's and 3a drives.

With the Arneson customers, I do not hear of the porpoising problem. The Porpoising problem is indicative of a lot of rocker that was used to get these boats to carry themselves and this is goes very well with the Arneson setup and regular rake propellers.