Best Drive for high power heavy 27' application??

[Maxumus]

Guys,

This is my first post so I just wanted to say hello and thanks in advance for any advice or guidance you may be able to provide.

Im in the horsepower business (cylinder head designer/engine builder) and I have a Maxum 2700 thats just dying for more power. Currently running all stock engine (300HP mag 350) hooked to a Bravo III drive with 22 pitch dual props. Boat goes 38MPH on the GPS....40 trimmed with a tailwind....LOL

Project this winter is to install a very well built 615 CID BBC engine that will make 800 TQ and probably low 800 HP at the crank (I will be dyno testing this engine to confirm). I could really use some input on a drive that would work the best and give me a reasonable chance of not breaking if I dont abuse the throttle getting up on plane (I believe that where the drive is probably loaded the most). I am looking for much improved planing speeds....would like to cruise at my curent WOT speed or slightly greater (say around 40-45) and it would be really fun to stretch her legs occasionally at WOT hoping to see close to 70 MPH or so (any input on the likelihood of that with the right set-up?).

Considering it does almost 40 now with only 300 ponies (and probably 350 TQ at best), the new 615 will tack 500 or so on both of these figures....some serious gains. The boat is a deep V hull obviously and not meant for any serious speed and while I really need to weigh it to be sure, I believe with the generator, additional audio/video equipment, and big motor, it will likely tip the scales at 8500 pounds or so.

Anyway....even if it went 60 at WOT but got on plane alot faster and cruised at say 3-3500 at 45 ish MPH, I would be pretty stoked. Not looking for a race boat obviously or i would have picked up something different, just a cruiser that can haul the mail and have all the creature comforts at the same time.

Would love yuor opinion on anything drive and prop related....it seems the consensus so far is a dual prop drive potentially bites too much water thereby is more heavily loaded and easier to break (makes sense) and that perhaps getting the right single prop drive is a better way to go (XR seems popular) for increased reliabilty possibly not getting up on plane quite as quickly as the right dual prop set-up.

Im fairly new to marine performance (heavy automotive performance backgraound) but Im learning quick and alot of the same applies....there is always compromises which I understand. Im looking to maximize my performance goals while trying to minimze as many negatives as possible. Reliability is more important to me than an additional 3 MPH top speed for whatever that is worth....

Thanks for your time/consideration and look forward to your input

Cheers,
Tony

[HTRDLNCN]

heavy cruiser+high horsepower= Arneson
just my .02c though..

[Maxumus]

Originally Posted by HTRDLNCN

heavy cruiser+high horsepower= Arneson
just my .02c though..

I just looked at their website.....looks pretty heavy duty but Im thinking first born just as a deposit.....LOL

Never heard of them (newbie)....looks interesting though.

-Tony

[PatriYacht]

If you think an Arneson is too expensive, you are going to have trouble with all of the other suggestions that are out there. 800tq is really too much for a Bravo unless you don't mind being towed in on a regular basis and spending 3-4000.00 on repairs a couple times a season. Konrad would be a good choice but they're about 20,000.00 when you include everything. Finding a different boat would probably be the easiest and cheapest option.

[RBeyer]

The B-Max Ht is rated to 950 HP and 14500lbs and is available with up to a two year warranty. Cost is about $15000 and requires no further modification, a birect bolt on.

I am on year three with mine and no problems. I could break a Bravo at will.

[Maxumus]

Originally Posted by RBeyer

The B-Max Ht is rated to 950 HP and 14500lbs and is available with up to a two year warranty. Cost is about $15000 and requires no further modification, a birect bolt on.

I am on year three with mine and no problems. I could break a Bravo at will.

It will swap right in place of my BIII that I have now?

Looking quickly at some literature it looks ideal for a high torque application. How is prop availability....same as the XR props or does it take something made specifically for it?

Thanks for the tip.....this is the kind of stuff that makes the message boards invaluable!

-Tony

[hotstang46]

I went through the same thing. Mine was with a new boat that was already rigged with all new Imco drive stuff. It is really my first NEW boat (still waiting in CA for delivery, hopefully ready in the next week ) so I did tons and tons of reading.

My boat has more hp and tq but with the levels you want you're in the same situation. Go arneson and fork out the money right away. Otherwise you will bleed it out slowly through rebuilds, replacements, and tows. At best it seems to be a crapshoot even with the best of the two, the B-max and Max Machine. If you truly intend to keep your boat for a long time, which it seems you do, there is only one choice. Shame on Mercury for not producing a viable product


the potential list of advantages.
-More speed vs bravo
-better efficiency + better gas mileage
-piece of mind by virtue of unbreakable reliability
-cool rooster tail.
-a company and a contact (rik) to help stand behind the
product if there is a problem

[ToMorrow44]

Seeing that you're in Valencia, its worth your time to go talk to Teague. They can recommend some various options for you and get you pointed in the right direction.
-Tom

[Perlmudder]

http://www.offshoreonly.com/classifi...o28713-en.html


right here and call it a day!

[Gladhe8er]

Konrad should do the trick.