Hi all, I would like that someone will help me cause I am stuck wheather I do trim tabs or not. I have this scarab 22 with an upgraded 502mpi in it, now my problem is when I'm running 70 + the boat tend to chine walk Now I was told to do trim tabs, yes ok which size?? 17" or 24"?? Do they solve the problem or not?? I only want them to for stability at WOT. Now, another friend told me not to them cause they drag and you loose mph, is this right??

Please help

YOU WILL LOOSE SOME SPEED BUT GAIN STABILITY.
DO YOU HAVE FULL HYDRAULIC STEERING?

I agree...
FHS made a difference in my tug.

While on the trailer, if you can grab your outdrive and move it side to side (port-stern) then you may have a stability issue that should be addresed before going to the tabs. Just a little bit of slop will cause tracking problems at the speeds you are running.



btw, imo the 17" would be sufficient on a 22' speedboat.

Thanks Guys, So I had dual ram add on steering and now i moved to a full hydraulic Mayfair steering, Didn't yet give it a run yet with the FHS. So should I give it a run and see how it goes?? As regarding the drive there was no movement cause I had just put in a new center pin and overhauled it with new O rings gaskets etc.

If your boat chinewalks,the things that will help correct it are usually as follows: twin ram full hyd steering,getting rid of ALL play in outdrive (loose gibal pins/pivot pins),if that doesn't help ,and it sounds like you have already done this,then you may need to make sure hull is uniform in shape/angle on each side of your pad and vee. As a last resort mounting a set of trim rabs PARALELL to the water,not boat hull will help. My 272 baja with mini pad chinewalked between 70-75 after you were no longer acellerating,even with twin ram external,going full to the helm eliminated 95% of it so I think you probably fixed it with what you just did,Smitty

Is it difficult to control the chine walking using steering input ? I have had fast speedboats with big outboards that chinewalked a lot and I could always control them by steering in the opposite direction. You simply learn to keep the balance by use of the steering wheel. I think it is great fun to control chine walking, the Formula that I have now is boring in that respect.

Ok Thanks, So the ideal thing that I will give a run with full hydraulic steering, and see how it goes.

Thanks to all