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Kikwear
07-10-2001, 03:36 PM
Ok, sorry for all of the posts recently, but I just got the boat. When I get the boat up near 45 or so, it gets really unstable in anything less than a slight chop. At 50, it feels like it’s walking. Is there anything to make the ride less pants-staining? http://www.donzi.net/ubb/smile.gif Thanks.

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1997 Classic 16 5.7 Alpha One
White with red stripe

Riley
07-10-2001, 05:05 PM
What type of prop are you running? I've been messing around with different props for a couple of years now, and some make my 18 a lot more snakey than others. I'm finding it's a double edged sword with these hulls--More lift will give you better top speed, at the expense of stability and increased chine walking. But what's the sense in going faster if your boat is on the ragged edge of control?

I'm thinking that a good set of trim tabs would eliminate the chine walk and stabilize the boat at speed, but I can't as of yet bring myself to hang a pair of the damn ugly things off the back of my transom. Right now I'm content to give up a couple of mph in trade for hull stability.

Gearhead99
07-10-2001, 07:24 PM
If the drive is adjustable, tuck it in alittle. If you have tabs, set them down alittle. If you still feel unstable you have a couple of choices.

1. Buy a slower boat that isn't a Donzi.
2. Get use to it, it's called High Performance boating, and most, or should I say ALL of us LOVE the rush.

WOW !!!

jaroot
07-10-2001, 09:16 PM
kikwear,

i have the same boat as you... 97 16 w/ 350 and an alpha... white w/ red stripe... i find my boat chine walks excessively if you trim the drive out more than a couple taps of the button... and this really frees the boat up.. i've played with trim some and this is the best setting i've found.. the trim gauge doesn't even budge. if you want stable just leave the drive all the way in and the nose buried.. handles like it is on rails.. til you fail to quarter or take decent seas head on... then she gets to rolling side to side, sometimes severely if you have the power poured to her. can't say i have a problem with her falling to the left though like your other post talks about... really noticable list though if you have passengers on the left side of the boat becuase of the prop rotation and torque. i am turning a 19 P vengence at about 4700 - 4800 rpm on a tach i have a feeling is about 200 rpm off (no way a sbc idles as nice as this one at 200 rpm)... my motor is slightly tweaked also... 4400 in stock 2V form.

Kikwear
07-11-2001, 08:18 AM
Yeah, the boat lists kinda hard with just me in it. Oh well. I love having the Donzi. I’m used to the 60 mph speed from my 1100 ZXi. Just the Donzi’s a bit more wobbly. Guess it’s an excuse not to take anyone with me. http://www.donzi.net/ubb/smile.gif

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1997 Classic 16 5.7 Alpha One
White with red stripe

Captain's Call coming very soon...

ALLAN BROWN
07-11-2001, 10:42 AM
IN THE 60'S WE THOUGHT THAT THE PRACTICAL SPEED LIMIT FOR THE 16' WAS 53 MPH. WITH THE EATON "C" OUTDRIVE, IT WOULD CHINE WALK AT 53, GUNWALE WALK AT 54, AND THROW YOUR ASS OUT AT 55+.

BROWNIE

Kikwear
07-11-2001, 11:05 AM
I didn’t say that I’ve gone 60 in the Donzi, but that I’m used to going that fast on the water from the Jet Ski. I meant the Donzi gets wobbly at higher speeds. What is the top speed with a 5.7? Only 53? I hope that’s not all she’s got. You know on another note, I have 1979 Wellcraft 19.6 Cuddy with a 898 305cid (which by the way is for sale). On the lower unit, the zinc above the prop has a little mini skeg, white the Donzi’s Alpha unit does not have the mini skeg. It’s just a flat recessed zinc. Could this affect drivabilty if I change them out?

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1997 Classic 16 5.7 Alpha One
White with red stripe

Captain's Call coming very soon...

[This message has been edited by Kikwear (edited 07-11-2001).]

Riley
07-11-2001, 11:45 AM
Brownie, what is the practical speed limit for the 18' hull, without trim tabs? How about with tabs?

BERTRAM BOY
07-11-2001, 04:05 PM
When I was in Forrest's boat, we doing well over 60( 64 on GPS) and it NEVER got that unstable. I'm not sure how different the hulls are , but I'm sure he can steer you in the right direction.

Forrest are you there?

BERTRAM BOY

Forrest
07-11-2001, 04:13 PM
Yea Cliff, I'm here. Let's steer 'em to the other thread (http://www.donzi.net/ubb/Forum1/HTML/002162.html).

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Forrest

BERTRAM BOY
07-11-2001, 04:30 PM
Ahh yes.... I see

Scott Pearson
07-12-2001, 06:56 PM
OK....I have about 17 hours on My 1968 18 and I can give you guys some info on how my boat has been handeling. Im still getting use to it but its coming along.

I have a SBC making about 325hp. Alpha Gen 1 with 1:5 ratio and power steering.A Mirage 23 pitch prop. I raised my X-Dim. 1 1/2 inches. Still kept port steering. I have 12x12 Bennett duel accuatior (Spelling)SportTabs.

Ok...I havent really opened her up...Still letting motor break in. But I have had her up to about 62-63 MPH not GPS with one other person in the boat. It gets on plane right away. Get it in the mid 50's and trim the tabs a little so she evens out then bump the drive up a little and it climbs right up there. At 62-63 MPH its turning around 4500 rpms. Not an ounce of chine walk.

I'm sure when I open it WOT she will react the same. This thing is VERY STABLE!

I'm sure it has a ton to do with how everything was set-up in the boat. For those of you who have seen my 18 you know that everything is perfect.

Just some useless info.....

(NJ)Scott

Kikwear
07-12-2001, 07:07 PM
Does any body have tabs on their 16? Wouldn't Donzi have put them on there if they thought they needed them?

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1997 Classic 16 5.7 Alpha One
White with red stripe

Captain's Call coming very soon...

avk
07-12-2001, 10:23 PM
I have a 1999 Clasic 18 with a 5.7 efi. First I must tell you that I am using the boat at Lake Tahoe at 6200 ft so I am a bit down on power. When I first used the boat there it was generally very good but at speeds over 35mph it would want to porpoise and the only way to keep it comfortable was to keep the drive holding the bow down. 45mph was a speed that required full attention. By listenting to this site I decided to install tabs (Bennett) and what a difference! Now at 45 mph the boat is steady as a rock, even the wife will drive there, and the Alpha drive is running in the neutral position. The indicators on the Bennetts are showing that the tabs are about 4 degrees below the plane of the hull bottom. My best speed (GPS) at 6200 ft is 48-50 mph. I don't think I would want to do that without the tabs. The C18 has become an extremly stable boat and I cannot speak highly enough of using tabs.
Alan

BigGrizzly
07-12-2001, 10:44 PM
my sisters 1966 16 has the Eaton/Volvo outdrive, if we use the top hole( all the way out ) it will chine walk. in the middle hole its stable. Remember the old ones have a different set up on the botton lifting steps. Myh 18 will chine walk if i trim it too highand I'm alone. That boat has a Volvo 290 drive with a 425 hp Ford 351 Clevland. I am using a Ron hill thrasher prop on that one. Both boats have standars X dimentions.

Randy

jkeefe
07-13-2001, 08:10 AM
Kikwear,
I also have a 1100 zxi and a Donzi 16'. The
Donzi is not as quick, but alot drier ride.
The 16' will porpoise at around 30mph, but
just increase speed and trim as needed. I
prefer the handling with two on board, but
even in a moderate chop at 52-54mph it can
get pretty stimulating. When riding the zxi
your jetskiing, when enjoying the Donzi your
not boating you are Donzi-ing. Sit down,
full throttle, hang on and smile. Jack

Kikwear
07-16-2001, 01:51 PM
As I was looking at the boat yesterday, I noticed that the prop is a 19P. How does pitch affect the ride?

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1997 Classic 16 5.7 Alpha One
White with red stripe

Captain's Call coming very soon...

Sam
07-20-2001, 12:33 PM
My 96 sixteen runs 56-57 mph (gps) with a fairly stable ride until I get it trimmed out to far. Then I just get a bad ride and no more speed. As far as trim tabs, I wouldn't be with out them. They make all the difference in the world especially in rough water. Give me a shout back with any questions.
Sam