jmherbert

Chine walking can be 'controlled' to a point. On hipo outboards, they have hotfoot throttles and trim controls on the steering wheel for this very reason.

Takes practice at the higher limits of chinewalking with small inputs of throttle, trim, and steering.

KAAMA

iTrader: (1)

I currently have a chine walking problem with my 32' Active Thunder just after hitting about the 83mph mark. I have full external race steering, stock/standard length Bravo One drives (no nose cones) hung on Stellings extension boxes with lab finished Bravo One 4-bladed 32" props. The boat had a pretty good hook in the bottom that was removed. Measuring from the propshaft centerline, my drives sit about 3.5-4.0" below the bottom of the boat. I have the extra long K-Plane trim tabs and give it only enough tab just to take the chine walk out, but at the expense of speed. I have purchased some -2" IMCO shorty lowers that I am going to try in hopes that it might help with the chine walk problem---but as with anything else I guess we'll see.

By the way, this usually happens in dead calm, or relatively calm water conditions.

LarryD

first even at level the spray hitting the tabs helps, if your tabs are the 20" ones put on the 30's theywon't scrub as much speed ( you will have to put the 20" down more to get the same result) what you have to remember is on V bottom boats the faster you go the more the boat comes up out of the water and basically falls off its V less to balance on as speed increases ( and yes boats with pads have a wider balance area) the trade off is a harder ride depending how flat the pad is for example fountain has a deadrise to thier pad so is sort of a compromise whereas early velocity 30's ( a fast hull) had a flat pad and keep in mind the shorter lighter boat is going to get high in the water at a lower speed than a bigger boat. the prop work I mentioned works by letting the stern sink which will help the chine ( wider area in water to balance on) we test these things on the race boat on dead flat water so you can see consistant results ( alittle chop and the boat never chines) the longer tabs act like training wheels or out riggers and trust me they will help even at level if you start putting them down in calm water you will scrub alot of speed ( although with all your power you could run the drive in bury the tabs and just power though ) not very efficent
the gentle rock I wouldn't worry about all the phantoms and extreams do that someone even coined the phrase the "phantom dance " refering to that. at some point unfortunatly you will just run out of bottom and will be at a speed barier. obviously cats and tunnel boats and 3 points extend that threshold by widening there stance

Dave M

That may depend on the hull. My hull is the opposite. I chine walk more with a 3 blade.

MESABALANCING

I know this is nuts but when we used to run the factory boats my guys used to set up the bottoms so that they would chine walk at full speed conditions I was in the boat several times with them and they used to drive the chine walk out with the steering by counter steering and they claimed the boat was faster that way it was a hairy ride but it did run awesome we set a couple of kilo records and that wasn't bad at the time with an independent team with no factory sponsorship. Also from my experience I know many guys say to run the other drives on the market the Bravo lower was the fastest lower we ever ran we took a Bravo of one day three times and installed another drive to not mention the name and lost 3.5 mph on gps the y may be stronger and everything else but they are also slower maybe someone else has had the same problem. Good Luck Laz Mesa

Cobra1

I was thinking just the opposite. I thought that choppy water would start the chine by rocking my boat side to side. I was also thinking that the harder i held the steering straight the better. Thats why I'm never afraid to ask questions. I'm sure a lot of people reading this thought the same thing.

JIMG

there are many things you can do to help get rid of some of the walk. other than that if it is walking at 80 mph and you don't know how to stop it, you are running the risk of severely hurting yourself and anyone around you. you really should get yourself comfortable steering that walk out of the boat. it will make you a better driver. anyone who drives a fast v-hull needs to have some experience before just nailing the throttle. cats are more forgiving, but to some degree that is just a false sence of security before the boat gets away from you. by the way. ever been upside down in a boat at over 80? trust me it hurts. and if you are lucky enough to walk away, 20 years later it still hurts sometimes.

throttleup

It is possible that you are experiencing this because you are running at 4200 RPM which may be close to your peak torque. Therefore torque loading and potentially causing ill behaviors. So combating them and softening them would be the objective.

Julie

Cobra1

Julie, Thanks for the reply. But my peak torque is at 4700 rpm and 850 lbs torque. I will be calling you soon for a lab finish prop.

BenPerfected

Cobra 1,
Is the 80 MPH a new top speed? If so, you may be " running out of bottom" cause by the increased hull lift. In other words, you are only running on the flat part of the hull bottom without the inter strakes touching the water. I suggest you hang the boat on one strap and find the balance point (CG). If the inter strakes are equal to or forward of this point, you may not be able to get control of the chine walk until you lengthen the inter strakes. If the bottom set-up is right/perfect, i believe you should be able to reasonable control a 27" vee to 90-100MPH.