shifter

The multi-speed is the best solutution. We proved that in 1998,1999 and 2000. The seatek could do nothing against the other gas boats until we ran the multi-speeds. They had overdrive crashboxes but it is asking way to much of the motor to perform from idle/plane/ midrange/ to top end.

We were running 3 speeds in 98 and then 4 speeds in 99 and 2000. We were working on a 5 speed when they changed the rules. We had dominated pole position and races won the class 1 championship back to back in 1999 and 2000.

The multispeed is the way to go on a boat.

pat W

stirling

A few years ago I had a Schiada 21 river cruiser with a 800 hp BBC with blower ,this was a shaft driven boat with a V drive and a T 400 GM tranny , almost all of these boats are using a T 400 tranny from GM ,mainly used for skiracing ,for pulling the skieer out the hole .

In my Dodge diesel truck I have the transmission from Goerend ,with a triple disc converter ,mod valve body,billed input/output shafts .
The truck is making +- 550 hp and 1100 torque ( based on 1/4 mile ) not dyno,d .

Do you think this sort tranny,s can be used for marine purpose ?
The converter is not needed anymore ,like in the T 400 GM we used a spline drive from ,, Art Carr'' the casing is aluminium and not that heavy ,but is quite long .

If anybody can find a way to shift the trans manual....it might maybe work.

Maybe ,,Mastmotorsport '' can do the job ,they are going to build some sort crate engine for boats truck etc ,and they can supply an aftermarket diesel fuel ECM module to drive these Cummins electronics

The trans can handle a lot torque ,I even take boost launches with this 7500 lbs truck ,and no problems for now .

(By thinking of this above ,I had a V drive with a 48 % step up in gears on this boat ,but using propellors 15 and 16 pitch .

So maybe the rpm,s that the outputshaft is turning is too low with a diesel..)

HabanaJoe

Shifter,

I agree the multispeed is a great asset for racing.

My relucantance in them is from a repowering stand point and only because of length. I don't know enough about them but my impression of such a unit would add at least 12" to the back of already longer engine and probaly then have to have a driveshaft to connect to the outdrive. It probably would not fit into existing space then?

I will say this strongly - the best place to make money with small diesels is in the re-power market. Carig Barrie and I and even Mark McMannus (if he remembers me still) had these discussions many moons ago. People that brought their boats only will go through so many sets of engines before they give up on performance boats in general.

After the first engines go they usally put in another set of engines of greater horsepower. When those go a certain % will sell the boat. Those that re-power again want more Hp again and then have to change drives, etc, etc and when those engines go the boat is for sale, at that point they are disgusted because each set of engines lasts progressivly less hours.

To make a dent on diesel you need to be able that after the first set blows that you can then drop in a diesel that will give some performance increase and not require extensive re-work of the boat - if it does the price of re-power becomes too high and you won't have sales. If that second set of engines can give them that 1,500 hrs of use trouble free - you have a home run and will change the performance boat market forever!!!

With that said, people will have no problem then upgrading everything (drives, etc) for an even higher Hp diesel to get more speed if the frist diesel set does what I said they should.

This project itself is over 20 yrs old (started 1985) and at it's peak in the eraly 90's those assumptions were very valid. Looking at all the late model boats for sale with re-powers and all talk on here I think those assumptions are still valid for the average buyer???

Thanks as always for great discussions!

Joe Gere

ps mthill - my cell is 732-718-2711

shifter

A inline 6 motor end for end minus bellhousing is 42 inches long. b-series

A bigblock v8 is 33 inches long.

A bellhousing is 5 inches

A Velvet drive is 11 inches to the flange.

A 3 speed with FNR is 13.5 to the flange.

A 6-speed with an offset output is 9 inches to the flange.

It is just a packaging problem.

Who said anything about making money this is the marine industry.

pat W

Njawb

Is that like the 3-speed in that it includes FNR, or would you have to provision FNR separately?

HabanaJoe

Although we have never made money in the marine industry it might just be novel to try for once!!!

Our box fit into the #3 housing slightly and added only 6" , the trick was to close couple a Bravo drive. At that point you could almost drop them in?

shifter

That included the FNR. It is a completely new design.

There is transition happening slowly with diesels. Lighter weight and higher reving. I.E. Audi / Peugeot v12's This was done with the direct injection. As this begins to invade the current motors there will be a switch to the newer light weight designs. That means lighter boats and faster. With the lighter motors the hull can be redesigned to accomidate the lighter package. In theory you can rev a diesel to 9000 rpm.

It will take a while for the big companies to switch because they are already set with their tooling. They have made little changes by dumping the mechanical injection and adding a electric fuel pump system but the base engine is still a generator unit designed to run x-RPM for x-hours and sitting on the ground not in a vehicle. Big, heavy and durable and has its place, always will. Think hoe cool it will be when they start to incorporate the new designs in the bigger diesels.

With the increase in revs the torque will drop. Multispeeds will make up for that. Giving the lowend torque and top speed performance.

pat W

matador

You're right Pat ,Audi shocked the world when they won the Rolex 24 hrs endurance race for more than 2 years on a row with a Diesel power; they have a team that work together with lot of money and determination to make it happen.In the U.S, Diesel have not gain any respect in the high performance arena simply because the mayority of people dont believe on it,and there hasnt been a big company that would like to spend the big bucks and get this thing rolling simply for conflict of interest,so til then we'll be just a group of friends exchanging ideas in this forum....

Njawb

While I would love to see a marinized version of the Audi V12 that is in their Q7 SUV, to be fair to the other Le Mans prototype racers, the reason for the recent diesel wins is at least as much due to the rules differences for diesel-powered competitors as it is to any actual head-to-head advantage of the diesel engines over the more conventional powerplants.

Thanks for the reply, Pat. I agree with your vision of the marine diesel future completely, but I am curious as to whether 6-speeds may be too many gears. What is the advantage of having such narrow RPM bands when compared to something like a 2 or 3-speed transmission?

shifter

We ran 6 speeds with the class 1 boat in 1999. It is a great way to set the boat for the for almost any sea condition. Right now there is 6 speeds in a pick-up truck with a dmax why not a boat?

pat W