My latest Idea...what do you think

[Last Real Texan]

with all the projects going on I was getting some ideas in my head for the winter...Well here goes, find a nice late model 90 or above 22 classic that needs some work, Re-glass the transom to accept a dual drive set up , just like the west coast ski racers via an IMCO dual drive gear box and set it up with a 1200HP blower motor. The only thing I am unsure of is the back seat. I think I am going to have to move it forwad to accept the gear box, the tranny space is not an issue since I will be using stand off boxes for them. How much can I move the back seat forward and not get into trouble with the center of gravity...I am thinking it will be extremely stable at speed with the drives spinning outand easily reach the 110 plus speed to make it worth doing. I also think the acceleration would be out of this world and I would not have worry about grenading drives with the speed and power. I need some feed back here.

Tex

[VetteLT193]

holy crap :eek!:

On a serious note, if you run extension boxes on the drives it would shift the CG back, so pushing the rear seat forward shouldn't kill the CG overall.

Although, pushing the rear seat forward would probably render it useless... maybe do a 3 person bolstered bench seat in the front. Or make a modern day criterion with a long hatch area Vs. the long bow.

[BlownCrewCab]

If you adding the weight of another drive you will want to move the motor forward some anyway, unless you only plan on being on glassy water.

[maddad]

I think the extra weight and drag of a second drive would surely slow that setup down to 110.

[gcarter]

Cut out the rear seat, build a hard tonneau to cover everything.......

[TXDONZI]

I did a search for dual drive ski racers and got this. Here is your engine!!!

http://www.nizpromarine.com.au/the_engine.html

http://www.nizpromarine.com.au/images/DSC_1471a.jpg (http://www.nizpromarine.com.au/images/DSC_1471.jpg)

[MOP]

Sounds interesting, the 22 does require quite a bit of bow lift to get to its full potential. But with 1200HP I doubt if that would be an issue, Donn Tam said something about over coming issues with raw power! 1200 is real RAW!!! I have seen one race where several of the boats were running 1 into 2 setups no question way more stable, on the start some of them leap pretty much clear of the water with just the bottoms of the props chewing up the water.

[CHACHI]

I did a search for dual drive ski racers and got this. Here is your engine!!!

http://www.nizpromarine.com.au/the_engine.html

http://www.nizpromarine.com.au/images/DSC_1471a.jpg (http://www.nizpromarine.com.au/images/DSC_1471.jpg)
Need more beam.

Ken

[glashole]

would it be a big deal to cut the hull directly in half, and make the boat a foot or 2 wider?

[glashole]

I would think that the best improvement that could be made to any classic would be to make the engine hatch larger for better access :smash:

[BigGrizzly]

There ia plenty of room to put tranies in engine bay with no stand off box. The Criterion s are that way stock. Owners of these boats love the balance and ride This is a monumental project. Just keep thinking Butch that is what your good at.

[Last Real Texan]

There ia plenty of room to put tranies in engine bay with no stand off box. The Criterion s are that way stock. Owners of these boats love the balance and ride This is a monumental project. Just keep thinking Butch that is what your good at.

Not sure what you mean by Butch

[Last Real Texan]

Hanging two drives should not be an issue with this project, set them up in a staggered configuration and go with XR's but my question is does a Bravo care what rotation the input shaft turns? If not I can elimnate the need for trannys. I think Roadtrip SE said it best, it will take a ton of hull re-inforcing to be safe and sturdy, but that could be done with the deck off and beefier stringers and bulkheads would do the trick. I am going to investigate the gear box and its configuration and dimentions with IMCO next week and see if it is even possible. I think this could be a really cool lake rocket that would definatly surprise some people if I could pull it off. This by no means would be quick over the winter project but rather a year long endevour that I would take my time doing. The ultimate goal here is to have 2 boats, one to rocket around on and then a big ZF for the family outings, say something like a 35 ZF with a pair of 300xs motors.
I really think that a well thought out project like this could work and work well. And even at 1000 Hp should easily see 100 plus:shocking: and beyond.



Tex
I am seriosly considering taking this project on and really would like some serious feedback

[BUIZILLA]

my .02...

if you REALLY want to do something original and set the world on it's ear's....

which you may want to do....

make the existing rear engine area the ****pit...ala JS skiff style

then make the existing ****pit area the engine bay with twin engines and one drive... make the engine cover clear or green tint plexi, the rear driver/passenger compartment could be a bench seat with a single tunnel drive to the sterndrive or make the centerconsole a drive tunnel with a waterfall style split like the C5/C6 interior... oop's.. too many hints...

[blackhawk]

Wouldn't the IMCO splitter require the engine to move farther forward? If so that could help with the balance.

Would definitely be a bad ass boat when completed and I agree that some serious reinforcement would be needed to keep the boat somewhat safe.

[blackhawk]

There was a Magnum for sale in Charlavoix with an airplane engine and an IMCO splitter a couple years ago. I had pics on my old computer but I lost them when it crashed.

[Carl C]

1,000 hp will get you well over 100 mph with a single drive. Spend the dough on a racing drive and with even less motor you will have a stable 100 mph boat. I have heard from the best that a 22C can be safe and stable @ 100 with a single drive. You'll be adding a lot of drag and weight and will create an unnecessary Frankenstein:incredible:. All just my humble opinion of course:wink:.

[BlownCrewCab]

In allot of cases the 2 counter rotating props are better than a single behind big power. Prop torque roll is eliminated, torque steer is eliminated. You may be able to get a higher top speed with a single drive, But the duals will run fast (just a few mph slower) and be safer. it also gives you the option to spin them outboard and carry the nose better or spin the inboard and keep the nose down. These days all the top Drag boats have the twin prop just to offset the massive prop torque they experiance. If (once) you get you drive hights right, it will be an absolute ball to drive. On such a light boat I'd think drive failures would be few and far between.

Do It.

[gcarter]

my .02...
if you REALLY want to do something original and set the world on it's ear's....
which you may want to do....
make the existing rear engine area the ****pit...ala JS skiff style
then make the existing ****pit area the engine bay with twin engines and one drive... make the engine cover clear or green tint plexi, the rear driver/passenger compartment could be a bench seat with a single tunnel drive to the sterndrive or make the centerconsole a drive tunnel with a waterfall style split like the C5/C6 interior... oop's.. too many hints...
Kinda, sorta like this maybe????
http://www.donzi.net/forums/attachment.php?attachmentid=38072&d=1219537604

http://www.donzi.net/forums/attachment.php?attachmentid=16908&d=1135618568

[Pismo]

No need for 2 drives.

[BUIZILLA]

EXACTLY my point...

[BigGrizzly]

I think the idea is kind of cool, just to be different. However the expense would be on the high side. If you want to be different, a blown 572 with no drive belts except the blower drive. If I had the extra $ I would be on this like white on rice!

[Roger 1]

Are there any out there that are running a single #6 Speedmaster with big power?

[The Hedgehog]

I still like the idea of a 20 Cig with an Arneson and BIG power.

Tell Sam to get cracking.

[p729lws]

Are there any out there that are running a single #6 Speedmaster with big power?

What he said :) Find a deal on a number 6 drive and start building the motor :shocking:

Dan

[Mr X]

Tex, did the thread get side tracked??
What is your ultimate goal......to run 100 MPH or rig it with twin engines?

[Last Real Texan]

Tex, did the thread get side tracked??
What is your ultimate goal......to run 100 MPH or rig it with twin engines?
To do something different and run it over 110 and be stable, accelerate like a rocket and do it all on one engine with some drive reliability with big power. Have some insight?

Tex

[Planetwarmer]

Do a turbine powered 22C! Lots lighter and lots more power. Since $$$$$ is no object. :propeller:

[The Hedgehog]

I think that his goal is to go well over 100 mph. I have seen some video of ski racers with similar setups. They use counterroating props like Blown Cab said.

If he ran a splitter box but used XR's there would be no need for trannies. He could run the drives close like in a staggerd setup and would just have to bring the engine up enough to accomodate the splitter. Hopefully that would offset the weight of the extra Bravo.

The power....well I am thinking a 598 with a 5 litre Whipple. It would need some top shelf parts. Tuned right you could make 1,200.

It would not be faster than a # 6 or Arneson but should be much more stable.

[BUIZILLA]

boy, are we in dark uncharted water's now... :hangum:

[SilverBack]

I think it would be a really different boat!! I used to blow off advise about the uncharted waters (Buiz told me that too) and get a different hull if you want to go that fast (MJW) but I wish that I would have listened now!!! I love Donzi boats and my last 3 have all been Donzi's but I would have been way better off in a diffent hull. We get these boats running faster than they were made to go and then worry about chine walk and getting out of shape. DW did the same exact setup that I have on an eliminator and you could run 115 mph and hold a drink in your hand while you drove it. You get the ZX within 25 MPH of that and you have problems with white knuckles.

Maybe you could split it down the center and make a 22 classic cat!!


It was before my time here but GEO got an x-18 to run something like 118 mph with a small block and an arneson.

Why not do a 22 with an all aluminum 698 CI big block with a quad rotor Whipple and an arneson. I think that would be a lot cheaper and you can keep the engine where it is. Keep your CG. Put the trans in an extension box and you will still have a bulletproof drive.

It would be like the big brother to the X-18. It would give a viper a good run for it's money too. :propeller::propeller::propeller:

[glashole]

We've also talked about a blackhawk boat with the arneson drive as well

if you couldn't find an original blackhawk boat, why not make the changes to the hull of a classic (if possible)

[cutwater]

So, is the main goal in this to go fast or to have 2 drives while going fast? I like the idea (however hard it might be to implement) because I would think it would be less of a "handful" at those speeds if you had two drives.

[blackhawk]

If money is no object then I love the idea of a 22 with twins. :yes:

[BUIZILLA]

so.....

do you start with a std hull or a blackhawk hull??

[Last Real Texan]

so.....
do you start with a std hull or a blackhawk hull??
Good question...Spoke with IMCO today and I was refered to a ski racing guru to talk further about set up and problems encountered...I will have more info at the end of the week.

I still have not ruled out doing a 20 FT cig with big power and an undecided drive package.


Still just researching all of this stuff and trying to make some educated decisions on my keep it forever kill the resale value:hangum: project

Tex

[BlownCrewCab]

I'd do a 24 Cig before a 20. When we where at AOTH I was in the back of DonziRacers 22 Donzi, There was one of the 20' Cigs running next to us and he was Airborn, chine walking, Having to back off and play catch up just from the Chop from other boats (we where going 65mph) I'm sure his boat topped out allot faster than 65, Maybe he wasn't an experianced driver, but Toms 22 Donzi (with a smallblock) smoked that 20' Cig in the chop. I Know Phil could have (and did) whip us, but he's very experianced. (and I think Phils boat actually flies across the water without touching it)

[blackhawk]

NO WAY I would start out with a Blackhawk hull if you pursue the twin drive setup.

Now if you went with a single Arneson the Blackhawk may work well.

[TREYSTJOHN]

Balance, ie CG and prop lift for any hull (even more for the round transom, large rocker 18/22c hull) is critical as GEO had no trans, lightweight heads & exhaust and it still took a lower foil on the Arnie and the new funky merc cleaver to get the boat to settle down and go fast. I don't think the 22c with 1200hp and any drive(s) setup would be stable/safe and hold up without major reinforcing and bottom reconfiguring. We did a lot of work when Reggie first came out with the 10 meter in 1983 with 850hp twin turbo/carb gale banks motors in front of #4 drives with 73c trans. The boat would not go above 98 without going into severe/scary chinewalking and transom slide. It took the factory 100's of hours of hull work to get the boat to 110 safely and when all was said and done it was determined that the additional lbs of the #4's and the 73c's was just too much rear weight for a 10 meter. A couple of years later years later with 650hp engines and #2 drives & 72c's and a similar wide strake hull we were able to go 104 safely......that being said, it would still be cool as hell and probably pretty safe up to about 90.