22c unruly over 70mph?

[Alexandre]

I just read somewhere that a 22c is unruly over 70mph.
I just bought a new engine and I will test the boat in a few weeks on the sea. Should I be afraid ?
Thank you.
Alex
SEE CIFICA TIONS 550 HP/S400RPM
Puissance: 550 HP / 5400 RPM
Cylindrec: 502 CII) (8.20 Lit.)
Rapport VoluntCtrique: 9.3 :1
Bloc Moleur: GM/Mercury 502 Block 4 boulons Gen.V
Vilebrequin : GM4.00 “ Forge 4340
Bielles : GM acier forge. Bouloas 7/16 ARP 4340 190000 psi
Pistons: i.E. Forge .090 dome
Segments J.E. plasma-Moly
Culasses: GM rectporl 340 cc
Soupapes Mm.-Ech.: Manley 2.25” 1.90”
Ressorts de soupapes : Crane Cams Special
Arbyc A cames: Crane Cams Hydr. Roller Special
Poussoirs : Competition Cams
Culbuteurs: Harland 1.72
Plaque cl’admission: Mercury 500 HP
Pompe Ahuile : Melling HV 90 psi
Carburatour: Holley 850
Carter d’huile: GM S Qt.


http://www.quadriracing.com/assets/images/db_images/db_DSC005671.gif

[Pismo]

That rounded keel on the 22 does make it roll around over about 70-75mph. You should be above 75mph so make sure your steering is very tight or even better get external full hydraulic steering.

[Alexandre]

That rounded keel on the 22 does make it roll around over about 70-75mph. You should be above 75mph so make sure your steering is very tight or even better get external full hydraulic steering.

Thank you, I have a 23 mirage plus on bravo one:

[Alexandre]

Thank you, I have a 23 mirage plus on bravo one:

It's a 1988 22c:
http://www.donzi.net/forums/attachment.php?attachmentid=26524&d=1168341190

[Morgan's Cloud]

[QUOTE=Alexandre;444279]I just read somewhere that a 22c is unruly over 70mph.
I just bought a new engine and I will test the boat in a few weeks on the sea. Should I be afraid ?
Thank you.
Alexc
I'd be afraid of doing WOT tests at over 70 in a 22 footer "on the SEA" ...
Keep it to inland waters/bays and you'll be ok ... just make sure you're running the right prop . There's PLENTY of info on that here !
Steve

[mjw930]

You will need to move up to a 27P Mirage Plus along with external hydraulic steering. Neither one of these is option in my humble opinion.

Without the prop change you will bang the rev limiter at around 64 mph and if you don't have a rev limiter you will blow the motor.

Without the steering you will find the boat is difficult at best to handle when it gets over 65 mph and can actually be deadly if the tiller arm or gimbal decide to break under the excessive load.

Enjoy the new power but make the additional changes to keep the ride safe.

[MOP]

Please post you actual cam specifications, in looking at the photo of your engine the exhaust risers look a little short for a high performance cam. There is a chance you will have reversion meaning you will suck water vapors back into the engine. There are several very knowledgeable people that will know if the risers are to short for the cam specifications, would be a shame to damage the engine.

Phil

[Pismo]

I agree on a bigger prop, a 27 MiragePlus sounds about right. Find one on ebay or OSO. Yes I hope the LSA is 112 or higher. Nice boat, should go good.

[MOP]

Is it my eyes or was that boat originally a small block, if so the exhaust outlets will not match up to the big block.

[Sam]

It's a 1988 22c:
http://www.donzi.net/forums/attachment.php?attachmentid=26524&d=1168341190


What's up with the Mich plate on the trailer or is this not your boat ?

[Carl C]

Since you already have experience driving this hull you will be fine. It's good to see a French Donzi bro here. Good luck with the project.:alligator

[justleft]

That manifold and carb may not fit under a stock hatch.

[BigGrizzly]

I would rethink my prop selection. there are better handling props out there. 75 with the right prop is a cake walk.

[Tony]

Over 70 in my boat is a cakewalk, thanks to the DP and integrated hydraulic steering.
I'm often thankful I don't have to enter the "myriad of props for a 22c" discussions!
:beer:

[mjw930]

I would rethink my prop selection. there are better handling props out there. 75 with the right prop is a cake walk.

Actually, I don't think he's even made a prop selection. Sounds like it's the prop that was on the boat when he bought it.

BTW, Saying there are better props without some suggestions isn't all the helpful......

[roadtrip se]

Maybe a few.

Try the 26 and 28 Precision TXP for a three blade...
My one experience with the 27 Mirage was death defying and scary. One bottle of Sauza tequila split with my passenger at the docks and we were fine. The thing has a very small diameter and it was a disaster on my application.

Try a Hydromotive 27 and 28 for a four blade... Slower than the three, but more bite and handling.

If you want to go the labbed route, the Bravo One with some work makes an awesome mid-range and top end prop.

We run into the low 80's with full hydraulic steering and a good life jacket. Wouldn't do it without both. The boat is stable at these speeds, but you have to pick your conditions.

[Alexandre]

Maybe a few.

Try the 26 and 28 Precision TXP for a three blade...
My one experience with the 27 Mirage was death defying and scary. One bottle of Sauza tequila split with my passenger at the docks and we were fine. The thing has a very small diameter and it was a disaster on my application.

Try a Hydromotive 27 and 28 for a four blade... Slower than the three, but more bite and handling.

If you want to go the labbed route, the Bravo One with some work makes an awesome mid-range and top end prop.

We run into the low 80's with full hydraulic steering and a good life jacket. Wouldn't do it without both. The boat is stable at these speeds, but you have to pick your conditions.

Thank you very much everyone for your advice.
I bought this 22c 3 years ago and i import it in France.
i change the engine because 4 days after on the sea the last engine stop. here is a picture of the old engine.
I gave this morning your advice to the guy who is actually placing the engine in the boat and he told me that it was not necessary to add an external hydraulic steering!!! the one I have insight was enought!!!
I agree with you that it should be better.
I will think about it and ask some financial porposal.

[Alexandre]

http://www.donzi.net/forums/attachment.php?attachmentid=26523&d=1168341190

[MOP]

Standard steering is unsafe at higher speeds, also if you can post the actual cam shaft specification. I think the exhaust risers are a bit short for a decent cam.

Phil

[The Hedgehog]

I am with MOP and the guys on the steering and cam thing.

The Mercury 500 hp did not like standard Gil risers. Those look even shorter.

I know that it is not a 22 but my 18 started getting unruly in the high 60's. External steering made a HUGE difference. Yes, I could drive it that fast but it was a handfull

[MOP]

Would be a shame to destroy the engine over something that simple to undo!!!!!!!!!!!!!

[The Hedgehog]

Those IMCO Thumper risers empty the water right after the collar. I have a set on the 16 and they will not handle a big cam.

Those risers on the previous engine actually look better.

[Tom A.]

I owned an '83 22 Classic with a 585hp Vortec Supercharged 454mag and a Bravo drive. The boat ran right around 80mph with a 28" 4 blade. There is no way I would run a classic over 70mph w/o ext. hyd. steering. It is a total drivers boat over 70 even with the ext. steering. I would also highly recomend putting a set of tabs on the boat. If I didn't upgrade my boat when I did, that was the next thing to go on my 22.

[boxy]

Maybe a few.
Try the 26 and 28 Precision TXP for a three blade...
My one experience with the 27 Mirage was death defying and scary. One bottle of Sauza tequila split with my passenger at the docks and we were fine. The thing has a very small diameter and it was a disaster on my application.
I think I was in that boat......
Bounce, Bounce, HOP ....... :eek!: :eek!:

[Tom A.]

I think I was in that boat......
Bounce, Bounce, HOP ....... :eek!: :eek!:

You won't be bouncing around 1000 Islands this year. You have a pretty nice selection to choose from. I am getting the Piratecom headsets installed Monday.....& Adam says hello and he is looking forward to a night or two of :smileybo:
I like the new Avitar! I expect to see many of those in 1000 Islands this year! I will bring plenty of Jack.

[boxy]

Sweet.....

Tommy are you going to be anywhere near Typhoon on the weekend?