zf transmissions??? what model cats???

We currently have Cat 3126 T/A @ 420 hp each. We ran 3116 T/A @ 350 hp each from 1994 til 2004 (and sold them for 1/2 of new). I stick with Twin Disc tranny's (MG 5061) because they are associated with Arneson and a staple around Cat dealers. Ratio 1.15 to 1 (almost straight drive). 4 Blade props are 20 x 25 and have been "tweaked" several times. I could get more speed with differeent prop, but these deliver same performance with 300 gal fuel, 6 people, loads of gear as they do when empty. I really like that. I have had other boats with big block gas (albeit many years ago), there is just no comparison. We run these hard. Sometimes go fishing 75 miles each way, 3 days a week and only lift the hatch for a peek. THey are nearly maitinence free. These current engines are 9 years old with about 1200 hours and have only had a starter replaced on one engine. Last year during a fuel tank replacement I pulled the engines and took back to Cat dealer and instructed him to do whatever he would do if he owned them. Cleaned turbos, coolers, zincs, belts, hoses, fluids, filters, and a great paint job. The bill was under $3,000. I am sure other have good exp with other diesels but IMO Cat is hard to beat. BTW the guy who bought my 1994 Cats still uses them today for charter fishing.

I am very happy with the yanmars I change the oil as needed and other than zincs and preventative maintenance, like sea water impellers, the motors need nothing, they use no oil and they just always run great, 420 hours so far.

Happy with my trip 480 Yanmar's as well. Think we are at about 625 hrs now. I have a lot of confidence in them yet.

Bob

As Joe said ...... . These guys ran strong and did not look out of place at all with their 2nd place finish. Congrats.

http://farm9.staticflickr.com/8204/8...a92ee6fb2d.jpg
Diesel sport boats by bobthebuilder707, on Flickr

my cousin has a 38 Magnum, triple Mercruiser 7.3 (powerstrokes) slightly tweaked with diesel Bravos
22,000lbs with fuel (600 gallons in hull total+aux 100gal if needed ) , runs high 60s full fuel.. Its a beast in the open ocean ...
Gets amazing fuel mileage..

I'd love to see a pic of those triple Powerstrokes.

The weight of the full cast iron diesel options is probably enough to frighten off many builders. 38' at 22k lbs sounds more like a large cabin cruiser than sport boat. My single comes in at 4500lbs empty, in a 21 foot ski boat config. That's even with aluminum heads, which I'm not aware of marine diesel manufactures offering up yet. I love Yanmars, when I buy a sailboat it will have one. But feel the horse power per pound is a bit low for go fast configs. Here is my Dmax before all the added garb. Mostly aluminum outside the block.

http://www.altfuelsgroup.org/picture...mal_photo4.jpg

Joe and Bob, I am a bit young to remember any big diesels holding their own in SBI, but I could see a comeback on the horizon . Did they also dip the rub rail under in turns like some pics I saw posted of that Italian boat? BIG TORQUE>>>

Technology rules in racing, and the lines between automotive and marine use are quickly blurring, Who'd thought Lamborghini engines could sound so good on the water either? The new diesels are going on a weight diet, while output is going up. I bet this little VM Motori 24V 3.0L finds its way into a boat soon. Only 500lbs bare, spins 5k, and Gale Banks thinks they can get 600hp out of it race prepped according to Diesel Power.

What I really wanta see is someone drop a pair of MB's all aluminum 3.2L V6 Bluetec's in a under 30' boat and wrench on them a bit.

-K

I almost can't wait for 40 or 50 diesel powered fast boats to show up on a poker run. Only the three in front will be able to see .... and breathe.

this from a guy with 300x's!!! :lolhit: I bet your engines smoke way more than mine

I don't see any smoke do you???
https://sphotos-a.xx.fbcdn.net/hphot..._1254591_o.jpg

No, but if I were behind you, I could smell the diesel for 7 or 8 miles. No offence I just think they belong in trucks and busses. The new whackers are great,and don't smoke, too many $$ to put in an old boat.