K Plane installation
 

Hey Boat people,

I am going to be putting a seet of 380S k planes on my little floaty toy..

Anyway, I am curious how far from the side of the hull I can mount the tabs, as I still have my Silent Thunder Platform on the transom, and I also have two U bolt through transom tie downs that attach about 4 inches in from the side of the hull. This would place the centerline of the tab about in line with the outer most lifting strake that goes all the way to the transom. Or, the outer edge of the tab would be at least 4-6 inches from the side of the hull.

In addition, should the tab be mounted perpendicular to the bottom of the hull, or should it be mounted perpendicular to a vertical 90 degree...

I ask, as I have seen K-Planes mounted both ways, and there has to be a reason.... I would like to know what they are....

Comments and opinions appreciated from all...


Need to resolve this before I start putting holes in the floaty toy... ;)

Thanks,

Richard

380's is way too much tab for a 24' boat.

Point taken.... What about a 27 foot boat...?

Still overkill. Most 38's still use 280's. 380's are for 35+ foot boats or maybe smaller race boats. Mount them at least an inch above the bottom if you use them. Not sure how far out on the sides.

The bottom plates are completely interchangeable with 280's though.

the 380s are a bit overkill for that size hull, but if you are careful, they will work....I would not mount them much over half inch from the bottom because the angle of entry may be a little too steep....they are usually mounted parallel to the edge of the transom line....however, if your boat has a tendency to chine walk, then you can mount them parallel to the verticle 90 degree...reason being your outside edge will enter the water first and have a tendency to settle the boat....

if you decide to go with 280s, I have a set of 280 plates I will trade you for the 380s.

good luck

Hiya Griff,

I was being a bit sarcastic about the 27 foot comment.. I spoke at length to Formula, and they ran 380s on their 271 race boat... that was with a 2ft molded platform, which means the hull length was actually 25 FT... Not much more than 24.2FT on my hull.. They also recommended adding an extension box to increase the X dimension, and use the 380s, with attention paid to mounting the tab. They did not want to give me specifics, for liability reasons...

So, I was trying to get some comments on the position, which you have given me, and it helps, as my hydrodynamic knowledge is limited..

Donz,

I will not trade the 280's for 380's, but thanks for the offer.. 280's are a dime a dozen, and 380's are not.. In addition, if I remember correctly, the tab length is different, the mounts are the same.. I can get a set of 280 tabs (bottom plates) as a spare for very little $$$, and try them as well...

Intresting that you say not much over .5 inch... My Bennets are .5 inch from the bottom, and the hull has a hook starting about 15 inches from the back of the transom.. My idea was to use the tabs as an extension of the hull with the extension box to increase the lift, and stability of the hull... I was told that if I removed the hook, the boat might chine walk at very high speeds.. However, it could be done, but involved too much work in my opinion to pick up the extra 4-5 mph.

What do you think about this idea..? Can you comment on what your race boats are running? As well as thoughts on the hook?

In addition, I will not be jumping many 3-4 footers in an offshore race.... :)

Thanks,

Richard

Hey Scott,

My boat's LOA and ACTUAL Hull Length is 24FT 2" including the 18 inch hook in the rear of the hull. Formula said their 271 race boat ran 380 Tabs when I discussed it with them. Their 271 (27FT 1" LOA) has a 2 foot integrated moulded swim platform, so the true hull length is 25 FT 1". This puts the difference in hull length between the 271 and 242 at an ACTUAL distance of 11 inches. NOT 3 feet, as the LOA measurement on the 271 counts the 2 ft moulded platform.

My boat has a Silent thunder Platform that is also 2FT long, BUT, IT IS NOT counted in the LOA measurements like the boat with the integrated, moulded platform...

In addition, my transom does not have a notch... The center lifting strakes stop extending back to the transom about 3 feet from the edge transom at the underside of the hull. However, the outer lifting strakes extend all the way to the back of the transom along the hull bottom..

Clear as mud...?

Richard

hell, they put 380's on 20 ft cigs....

Richard,

If you are putting a box on the transom, the 380s should work fine. The only thing you need to worry about is sinking the tabs too quickly in a turn or in rough water. You will definitely feel the 380s back there. I get from your statements you are not planning on running the boat hard or in rough seas. Although thats kind of inconsistent on wanting 380s and a box.:D:D Unless you really need the additional couple of MPHs, I do not think it is worth the money to remove the hook. Just go out there and enjoy the boat. I reiterate, do not go over 1/2 inch on the placement as I think you will have detrimental effects on the boat.