GABLES

Am UK based so maybe delay in replies due to time difference. The problem I am having is at a GPS measured speed of 78mph she starts to chine walk and progressively gets worse. I have WPM add-on hydraulic steering and biscuit tin trim tabs! I am not sure if it requires full dual hydraulic steering system or a set of performance 24" long tabs - or both!

Please can somebody advise me before I get wet!!!

bluellama

What are you running to get a 26ZX to 78mph ????

GABLES

I am running a much modified 502 EFI with M3 procharger and XR drive on a standard 30" Bravo (for test purposes) but haven't managed to finished prop testing due to problem. Still have some left yet.

bluellama

Nice set up. I would think you want full hydraulic steering. The guy you want to talk to is Frank Civitano from Typhoon Performance Marine. He ran a highly modified 22zx, and is currently running a modified 26zx.....

Bryan Rose

Drive through it........after some seat time............................Sounds bad but it is true. I have a twin step 27 ZX with big power ( 500 EFI w M3 SC ) and my boat chine walks from 75-79 mph, once it reaches 80 it gets up on the pad and keeps on accerating to 84-85 mph smooth as silk....................get it up on the pad and it all seems to come together, if you have more left in it keep the faith and drive through it if you do not have anything left in the throttle trim and hope that you can drop the tabs with out scrubbing too much speed to settle the chine walk down. The first few times after I put the procharger on it was a little unsettling but I found with patience and prudence I was able to drive through it to the other side and find the smooth ride of the pad.

Note my chine walk was not to bad and I never felt at risk getting through to the other side.
Also chine walking is basicly the boat falling from one side off the pad and then getting on the pad and falling back to the other side and this creats a bouncing back and forth issue, some seat time and you should be able to control it. full hyd steering will work better also check the play in the drive ...it should have no play at all.

Bravo I prop 30 pitch hanging off an Imco Shorty
Best speed 85.3 @ 5300
All stated speeds are GPS
Bryan

LAKESIDE RESTORATIONS

Bryan stated it pretty accuratley, I too have a 26zx & have been behind the wheel of many other zx's & donzi's.. Its what I do..

If it is only a little chine walking try drive it out, if it is bad then you will need bigger tabs or planes.. Also what prop are you running? Playing with props can sometimes help as well.. Jamie / Lakeside

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GABLES

Dont feel comfortable to drive through the problem - it is a bit of a tank slap !!Hardin marine do a 23" performance set of tabs which taper to 3-3/4" at the tip or there is a 24"tapering to 8". Thoughts on which would be most suitable? Am running standard Bravo 30" which i seems to spin up but happiest trimmed out to 7!

LAKESIDE RESTORATIONS

If you are going to do that then you might as well go to the 24s already.. That is what I would do if It was me & I was going to add bigger planes.. Jamie

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GABLES

Cheers Jamie big is best! Guess I just needed a push in the right direction!!
Thanks to everyone for their input will keep you posted on final results
Regards Trevor

LAKESIDE RESTORATIONS

No problem.. Jamie

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