7 surface drives on boat?
 

Does anyone know what boat this is? Looks like it has 7 surface drives.

3 on each sponson and 1 in the middle

Is it an invisible boat?

sorry here is picture

They look to low to be surface piercing drives, I'd say they're simply propshafts with props below the waterline.
Have you got more pic's???

See ya,
Kelly

wow,7 props,what the hell kind of boat is that?

More pics!!!

must be a smugglers boat:lolhit:

notched transom - drives aren't low

They aren't drives. They are inboard prop shafts. Look at the bearing at the back of the hull. Also reg rudders. Surface drives turn. These don't. Just inboards like a big fishing boat has.

Trimax, BPM, and some arneson drives don't turn and they are considered surface drives. Either way my point was the boat has 7 props tied to at least 7 engines. So back to my original question does anyone know what race boat this was?

I took pic off a video I saw on YouTube, maybe oli can give us some insight I think it was a European boat.

One of Al Copeland's Skaters I saw in New Orleans had 5 props, two surface drives per sponson and an Evinrude 225 in the middle for manuvering around the docks.

I think it is 'Robur':

http://www.proprider.com/forum/showp...3&postcount=43

http://www.proprider.com/forum/showp...4&postcount=49

http://www.proprider.com/forum/showp...8&postcount=51

http://www.proprider.com/forum/showp...9&postcount=52

It's from the movie "Fast Boats Hard Water"

Jeff

Surfacing drives do not need to be steerable nor trimable. Those are definitely surfacing propellers and the shafts may have come out behind a deeply notched transom forward of the photo area. Neither Arneson, Buzzi, nor BPM own the "surface drive" concept. This looks almost exactly like the setup one would see on an inboard hydroplane or drag boat...set up to "surface" the prop shafts.

What was the concept of that Rubar boat? 7 powerheads running to gearboxes then to shat drives?

Olli you are right it is Rubar. If you look at the 21:14 mark of this video you can see it. Looks like the outboards come straight through and they just extend the prop shaft....

http://www.youtube.com/watch?v=aKtVKAk3SYo

Anything running at the surface is a "Surface Drive". Of course this ranges from an Oar, a Paddle Wheel to even a Bravo or an Outboard and lets not forget the first surface drive, ones own hands.

Unless you submerged your entire body.... :)

You've gotta come up for air eventually:D

Rich, totally different subject, but what can you tell us about the OHC engines used on the 48' JJ?

With the BBC being stuck back in 1960's for all practical design purposes, the BBC needs a good Over Head Cam head design and I saw something a while back saying you had installed engines which had quad cams.. Did they make good power? Reliable (trick question I know) were they basically BBC with different heads or a totally new engine?

Rik JJ Had those Batten Dohc engines we talked about. At least that's what I've heard.

RIK - I believe they were the Batten B-4 heads on a "stock" style block, they had external belts and pulleys to drive the cams much like a Seatek diesel does.

The B-4 heads did not have the advantage thought to be gained. Long stroke engines do not do well with 4 valves unless the rpm's are way up there and a BB can not rev high enough to take advantage of these heads. That is why you see more small cui, short stroke engines with 4 valve heads, they respond better to them.

The BBC can rev very well, the current SC class in SBI limits the rev's to 7K but they can spin a lot faster than that and if there was a good OHC head the engines could rev higher and live a lot longer; not to mention the power increase due to the higher rpms also.

RIK - my comments were in regards to the 4 valve heads, a OHC head would help greatly it to rev higher you're correct. But with the long stroke of a BB the 4 valves offer no real advantage in natural aspirated engines, in fact the lower rpm power is diminished and 7,000 rpm's is getting into the range where they start to work.

Either way I agree with you it's time to get past push rods!

mercury marine 1100 and 1350 have dual overhead cams and no pushrods ,i believe in the next 5 years,we will start to see more like them.

I agree, I think the overhead cams would be great for another obvious reason, that being it gets rid of the cam to crankshaft clearance which allows for different strokes. Also, I (not being an engine builder by any means) believe it will have less parasitic loss of power over the push rod design, but GM keeps trying to prove everyone wrong. One hell of a great head design probable goes a long way to make up for the push rod geometry; once again, what do I know but it certainly makes ignorant sense:D

I just cannot believe that no one over the years has made an OHC head for them. Here is a 4 valve head but not OHC. http://www.valleyhead.com/thunder.html

I have to agree Rik. Whilst I'm by no means an engineer with the ability to design something myself, in theory I can't understand why it hasn't been done yet (besides mercury only recently, and at a typical mercury inflated price). I can only assume head designers get so involved with re designing and improving what they already have that they don't think to go outside the box and design something that every other engine type has proven is superior!

They were engineered by Batten in Detroit. Batten created the "Quad 4" Oldsmobile engine and basically tricked up some aluminum heads off that concept. If memory serves...and it frequently doesn't...these were bolted to aluminum BBC style blocks. The motors with individual crash boxes were connected (one forward facing, one facing aft) through a "drop gear box" with "quick change" gear ratio options from 1:1 through 2:1. THis coupled to a single drive shaft per side running beneath the aft engine to a custom surface drive designed by Tom Wenstadt and built in Detroit. That drive train was awesome but the dependability of the motors was so bad as to be ludicrous. In most tests as you spooled up the motors and accelerated, you could see oil pressure dropping off on at least one or two motors to the point where the boat never achieved full throttle on more than two engines which, of course, were being held back by their counterparts. In its few races the motors were always detuned and limited to try and finish at least a few laps. In hindsight, Mercruiser 1000 SC's would have been a much better choice....or an engine development budget rivaling GM's to perfect an obviously embrionic concept.

Ah, the Quad 4 engine. My wife had an '88 Olds Calais with that motor. Locked up sitting at a stop light with 7K miles on it. Next motor vibrated your teeth out at idle.

Batten did a lot of work for Olds, Mopar, Chev, etc. They were an outside casting facility that could do jobs more quickly then internal operations which were geared to production.

Wannabe

This engine is supposedly a JJ 48 engine...

Rich your the one to tell us if thats correct

That looks like one of them, but for some reason the induction system looks different than I remember. Seems like they ran carbs for some of the testing. I do recall Donovan blocks being used.

In any event they looked a lot better than they performed........

like rich once said what works under a hood of a car does not work under a hatch of a boat!!!!!!! happy

wow... never seen that before. totally BAD A$$. can't believe DOHC never really caught on until now (1350) with big marine motors. I guess the tried and true BBC is hard to beat.

Were these ever put in boats?

Captiva- Its a V something? I guess we need an explanation of what it is and the old salts on here can tell you.

Wannabe

It's a ford dohc gaa. Sherman tank engine. They do show up in pulling tractors from time to time.

Aluminum block and heads,32 valve, 1100 cubic inches, 1000 ft lbs. torque at 2600 rpm and 525 hp @ 2800 rpm stock. Weighed in at 1400 pounds. That pick does NOT really gve you an idea of the size of it....

http://i202.photobucket.com/albums/a...rm/mustank.jpg

The biggest disadvantage to DOHC is the physical size. OHV motors package really well. I'd guess the 7.0L LS7 is similar in size to the 4.0L V8 in the BMW M3. Sure the bimmer has awesome specific output at 100+ HP/L. But in HP/ft^3 the LS7 probably still beats it, and crushes it when comparing TQ/ft^3.

In boat applications, the size and types of engine bays varies so widely. Their cant be general answer as to which is best. In a side by side application, a DOHC motor will need to be spaced further apart, or your block deck height needs to drop, reducing your discplacement.

For staggered and cat applications, go with the tallest decks, most cams and most boost you can afford!:D

I want to see pics of rubar. I couldn't get through the links to the prop site on my phone.

Those Ford tank engines are bad ass, but the problem I see would be getting them to run fast. You'd be looking a diesel like gearing with such a low red line.