No Pat You Got It Wrong They Still Scrub Speed When Lowered In Both Positions ..You Use Less Tab And You Have More Surface When Mounted With The angle Of The Boat ..Where As If You Put them Horizontal You Have To use More Tab And Your Only Hitting the tips On The Water ..Your Not Using The whole Tab ..Well Just theory

Lightspeed,
No doubt you scrub speed in either configuration when you drop the tabs. And I do share your opinion that mounting with the angle of the boat is better/more stable. And if you run with the tabs at neutral, it's like adding 2' to the length of your boat..
However, with the tabs mounted with the angle of the boat, and both dropped below neutral, they will act like a sea anchor and grab the water. Hold your hands like they are trim tabs and bend at your wrist; they will angle outward, grabbing the water like brakes.
Now with the tabs horizontal, parallel with the water, as they are lowered they push the stern up with a more vertical force. The tabs don't work together to cup the water so to speak.
I believe I do now understand why tabs are now sometime mounted horizontal. Anyone else buy into my theory?

Seems like a catch 22 to me... If a tab is mounted horizontal it will cause less drag when lowered but will also not work as well because of less contact being made in that lowered position. The way the theory was explained to me is very similar to what Lightspeed said, the tab is mounted at the angle of the hull to make contact w/ the water and influence the ride with as little down travel as possible. Think about this also: in either case the bow being forced down would cause more drag then the placement angle of the tabs in either set-up.

Well said Huntington...
So how are you going to have JC mount your K-planes?

Here we go again..........sure would be nice to get it right...........and than just repeat the process. Good luck Rob.

Gary,
It looks like JC had JD mount the tabs on your boat in the middle somewhere; a happy medium maybe?
JC runs all the boats that come out of his shop so he knows what works and what doesn't...

I started this thread to discuss the theory behind tab location and angle. I don't think we have in said that mounting the tabs more toward horizontal is wrong, just different...

Fountain Is Doing Well These Days In Races Maybe We Should Ask Reggie. Common Lightspeed Ask Him , Ive Seen His Helicopter In Your Yard. We All Know Your A Spy For Reggie Stealing Superboat Secrets From John.

Yea lightspeed, stealing all those TRADE SECRETS from JC, Shame on you !!!!!! lol lol

I am a believer in the "mount the Tabs flat", but only if they are 380's (long ones).

If you do this, you better make sure of a couple things.

1. Make sure your boat doesn't have a hook in the hull.

2. Make sure your engine is in the right place.

The correct "Center of Gravity" is very important, or else it will be an unstable situtation.

If done correctly, the "tabs flat" set-up will be faster...