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BacDoc
07-09-2002, 11:42 PM
Just got the new HP500 ( X500 from Marine power) installed in my 22'Classic. Machanic took out for test run and says he got up to 74mph ( not gps)at 4900 rpm this is with 25p prop . Says it got a little squirly at that speed and says the hydraulic steering I told him I wanted to install would fix that. My question is what he's talking about most likly "chine walk" and wouldn't K Planes help that not the steering. Next I found some used K Planes for sale that the guy says their a little coroded and need to be sand blasted and repainted. They are 280's he thinks and they are 15" wide and 20" long. Are these the right ones for my boat and can you buy these used or should I just bite the bullet and buy new ( anyone know where to get a good deal).
Thanks,
Dan
PS Do you think the top rpm at 4900 with the 25p prop is because the engine is new and needs to be broken in. with a little time should gain a few hundred rpm to get it to 5100-5200rpm

Greg Maier
07-10-2002, 05:31 AM
I have 280 K Planes on my 22 Blackhawk and they work great. You have to be careful because those big planes will really throw the boat around if they are not used properly. Even with the K Planes, I still get chine walk at 70+ mph. I was planning on installing hydraulic steering to take the play out of the drive. I was hoping that this would help with the chine walk.

Tom Davis
07-10-2002, 08:13 AM
The external hydraulic steering will do allot to help out the chine walk problem. It does two things for you: 1) it takes the play out of the drive and 2) it will make the steering tight and responsive enough to "steer out" of chine walking (this takes some seat time). The trim tabs will do little to correct chine walking as it happens. There are other benifits to trim tabs, such as planing, adjusting ride attitude, high speed turns, etc... they also make the boat think it is longer than it actually is in rough water.
Just my .02

blackhawk
07-10-2002, 10:19 AM
Tom is right. There are a lot other benefits from the K-planes. I use mine(280s) to keep the nose down a little in "confused" waters so it tracks straight. I would recommend full hydraulic external steering. I don't first hand about correcting chinewalk, but it seems like it would by tightening up the slop. I am getting ready to install full hydraulic on mine just for the safety aspect. Plus it looks sweet as hell! :D

BacDoc
07-10-2002, 05:50 PM
Thanks guys. From what I gather a stock 22'Classic that runs in the 60mph range is ok with stock trim tabs ( or no tabs)and the normal power steering. Start playing around with higher performance stuff ( higher HP engines,Blackhawk drive..ect)you need to upgrade to high performance stuff like K Planes and full hydraulic external steering.
Thanks again, I'll try and post some pictures soon
Dan

roadtrip se
07-10-2002, 07:19 PM
Dan,

One thing to add here. I would make these changes incrementally. Try the steering first.
Test. Still have issues with stabilility, then go to the k-planes.

Blackhawk boats respond to tabs a lot differently than the bravo boats. I know of several hipo Bravo boats that run the exact same size k-plane as the bennets and rarely find occasion to use them. My guess would be that the much larger 280 k-plane would not help and could end up being a liability on your boat.

Good luck!

Todd

Woodsy
07-10-2002, 08:04 PM
Dan...

I just wanted to chine walk in with my .25 worth..

First, the tabs that come stock on your Donzi, be they Bennetts or Trim Marine, are not up to the task of landing a 3400lb hull in rough water, nor are they up to snuff after 60mph. Why Donzi puts them on a $50,000 boat is beyond me... I broke one of mine this weekend! :mad:

The 280S K-Planes will DEFINITELY help a chine walk situation. All you need to do, is drop one tab just a little and you will counteract the chinewalk. The 280S K-Planes will be a bit large for a 22, but they will work really well with small adjustments. Tom is right, it will trick the boat into thinking she is longer.

Factory BlackHawk boats need the 280S K-Planes to get over the huge amount of rocker in the hull. Without the big K-Planes, those boats would not be able to keep the nose down. I really think the problem with these boats was way too much rocker..

As for the Hi-Perf Bravo equipped boats, they are running the smaller K-Planes with pretty good success. They really only use them to counter act the torque twist when getting on plane, and maybe just a touch in rough water so the boat lands nice & easy, without stuffing the nose (too much tab) or launching vertical (to little tab).

I agree with Roadtrip, go for the hydraulic steering first. But when you mount the hydraulic steering, have the shop mock up a set of K-Planes before they start cutting transom. That way you will not have any clearance issues if you decide to get the K-Planes at a later date. Many a Donzi owner has been dissapointed to find out the K-Planes won't fit on the transom because of the steering...

Another thought you might want to entertain is an extension box with hydraulic steering.. the farther the props are from the back, the better.

Woodsy :D :D

MOP
07-10-2002, 09:35 PM
K planes in the wrong hands can be real spooky, they can be and have been trimmed a shorter making them much more forgiving. do it right and you will hear Gee never saw that model. There are non stronger or more reliable. I can see some of you K plane owners squirming at the idea of hacking a them, I am also sure most of you are reluctant to thin foil your skegs which can all by its self give a decent boost in speed and relieve some prop tourque with no other mods.