Question about planing devices
 

I picked up a 221 Liberator at the end of the boating season last year and only used it a couple of times. It has a 468 Chevy and King Cobra outdrive. The previous owner installed a large fin on the drive to get it to plane quicker for skiing with his kids. The boat comes up on plane very quickly. I don't use the boat for skiing. Does the fin detract from the boats higher speed performance?

Ditch the fin and install trim tabs if planning becomes an issue. You can use Marine Tex to fill the holes on the outdrive.

I am not sure I agree. Tabs would be better for sure, but drag race outboard boats all use planning fins on the drive. At higher speed they are completley out of the water and I do not think they would slow you down at all. I think a small boat like a 22' it would not be a problem.

You have a 22' boat with a 468 CID Chevy and it needs a planing aid? I don't think so. Take it off now before anyone else sees it.:angry-smiley-038:

If you don't plan on using the boat for any water sports I would ditch it. The purpose is to get the boat on plane faster and keep it on plane at slower speeds for skiers.

I don't think it would negatively effect the performance, though.

Run it, remove the 4 bolts to remove the fin, do a back to back test run.

Agree it should not affect high speed performance. I just hate seeing these things on any boat. I should have stated such.

It will actually scrub about 2-3 mph off on top speed and they exert huge forces on the cavitation plate and cause them to break. O your boat with that much power you may not see as much of a speed drop, but on a 40-50 mph I have seen as much as 3 mph more with it off. And of course having the cavitation plate welded back on is always a joy too:angry-smiley-038:

Lose it, you'll be happy. Fill the holes with Marinetex or epoxy as someone else said.

I'll pull it off and fill the holes. Worse case is to put it back on if needed. I also think I can go a larger prop.

:cheer: Good call. Those things belong on 4 banger Bayliners and such that can't get on plane without some help! You can always have two props; A power prop and a top end prop.