Arneson on V Bottoms
 

Whats up everyone? I was wondering if anyone has Arnesons on there V-Bottoms. I heard that with the step hulls they do very well and get you quite a bit more speed. Like up to 6 mph more that other drives. How do they handle? Can you trim your boats properly and would you do them again?
Hunter

It's a step up from the sterndrives in every conceivable way. They are more reliable and faster. They also dramatically improve handling because they are actually meant to operate as a surface drive. Many manufacturers are now mounting sterndrives with such aggressive X dimensions in order to squeeze some more speed that they are virtually running in a surface drive mode. This adversely affects handling and general dynamic behaviour because Bravos, even with Sportmaster lowers are not meant for that. Not even SSM6 is meant for that. Arneson is not exemplary but it is much better than any sterndrive in that department. They can also be cheaper. If you are running around 700hp with a gas motor, you would need a SSM6 unless you're really looking for trouble. This damn thing is expensive. Instead you can run the new Arneson ASD6 which is a lot cheaper than the Speedmaster. In terms of speed over a Bravo sterndrive, I would say that the gain is more than 6 mph. For example, a Hustler 388 Slingshot (whose transom you can see in the OSO side column ads for Arneson) with twin KE 675s and ASD6s ran 110 mph. I doubt it would run 104 with Bravo or SSM6 drives for two different reasons. Bravos are penalized by the fact that they are not surface drives, their thrust is at a greater angle meaning a loss in efficiency. A SSM6 on the other hand is built so heavily that it probably takes 50 or more horses to move the cogs around. Arneson is much more efficient from that point of view. Next time you go to a boat show, find a boat with Arnesons and a boat with SSM6s and try to spin the prop and you'll see what I mean. It takes a lot more energy to spin a SSM6. I've experienced all imaginable drives: Alphas, Bravos 1, 2, 3, Volvo DPs, Speedmaster 3, 5, 6, Pulse Drive, Sea Fury, Levi Drive, BPM, Arneson, Trimax and while Trimax remains my favourite, Arneson is up there and I would never go from those surface drive systems back to sterndrives.

I have Kaamas on my Formula, which are also surface drives. I've heard they run about 10% faster than conventional drives. My heavy azz Formula will do 78.6 with twin 468's putting out somewhere between 450 and 475 a side. I doubt very seriously if it would break 70 with the then standard TRS drives.

The only drawbacks I've encountered are the fact that it is VERY sensitive to tabs. I almost T boned a sailboat during a poker run while moving the tabs. I think this may be due to less "rudder area" in the water. To combat that happening again, I just run with the tabs up all the time. I was told when I bought it to drop the tabs to take off, but I've found that it will get on a plane just as fast with the tabs up and I don't have to fool with them once I get up. The only other drawback I've encountered is the fact it won't stay on a plane at less than 30 to 35 mph. Once it comes off a plane, you have to pretty much start all over.

WELL, IT SOUNDS LIKE WE WON'T SEE A SUTPHEN IN SOUTH CAROLINA WITH SURFACE DRIVES IN THE NEAR FUTURE !!!!

I haven't done a lot of maeuvering in reverse, so I can't really say.

The props do stick out a bit and are sharp, but they are on conventional drives too, just deeper in the water.

I don't know about Arnesons, but I've heard all the gears and bearing in the Kaama can be bought from bearing places. The only thing you can't get for a Kamma is the case itself.

Don't break !!! check this out !!!

I saw some brand new Kaamas on ebay a few weeks ago. They had new 405 horse engines for sale for $5000 and would include a new Kaama for $2500 more. I emailed them to see if they would just sell the Kaamas and they said they wouldn't.

Even with the engines, it would still be a helluva lot cheaper than sixes! Then you could turn the engines for at least the $5000 and get the drives for $2500.

I didn't have an extra 15K laying around or I would have bought them.

When factoring the cost, don't forget the WOW factor that the surface drives bring.:)

Super Termoli/ sounds like you have some experience with surface drives. Is it feasible to mount an Arneson on a v bottom so are you able to get 2-3 degrees of positive trim angle on the prop shaft and still have enough of the prop in the water to get decent efficiency? I guess what I am thinking is, I believe the output shaft c/l is on a plane above the boat bottom by a couple inches. If you try to trim the shaft up you loose your water to the prop. Do you happen to know how close the c/line of the prop shaft can get to the bottom of the boat on installation?

Hi Bob. Just saying Hi from the worlds in Orange Beach. Call you tomorrow!!!:D

R....what are you doing on here???? Give Les our best! Give me a ring tomorrow. Now get back out there and enjoy Orange Beach! :)

Fred asked some great questions...also would be the one how the bravo to ad6 conversion is and what gains are to be had for the peso`s. It will be interesting what information comes from this post.
TOm

PS: Fred you are a
funny man
gr8 avatar

If I am not mistaken an asd6 takes the same prop as a #6 and the reason for poor performance in reverse is the design of the prop to move water to the rear and not forward like in reverse.

Also they do stick out from the back of the boat a good ways and if you think a #6 is safe to swim around think again. Youi can build a swim platform further out to cover the props but it will stick out about 3.5-4 feet as seen in these pictures

If I am not mistaken an asd6 takes the same prop as a #6 and the reason for poor performance in reverse is the design of the prop to move water to the rear and not forward like in reverse.

Also they do stick out from the back of the boat a good ways and if you think a #6 is safe to swim around think again. Youi can build a swim platform further out to cover the props but it will stick out about 3.5-4 feet as seen in these pictures

2

I Know of arnesons on a 37 OL with cat's and it does of all of 70mph all day long.

Arnesons being Twin Disc, parts are readily available in most places. If I can find parts quickly in Europe, then you guys in the US must be able to find them in a heartbeat. It is just a question of knowing where to look. Most people can find replacement Bravo parts in a second because they have been boating with those drives for a long time and have had a chance to visit all places which do repairs and parts. A bit of quality time spent with your Arnesons and you would be able to find a quality source of service and parts. Besides, yes they do break but when they do it's either because they have not been installed/used properly or because they have not been maintained properly. As far as swimming goes, cover them with a large swim platform, like on Magnums. This is where Trimax presents certain advantages as a nicely proportioned platform is integrated in the hull design. This platform has molded steps and grabrails to help you get in and out of water, increases the rear running surface at low speeds which makes the boat able to plane at 15 mph and also has integrated ventilation ducts so you don't have to drill your SSM6 or weld tubes to your arnesons. Attached is a photo of a Trimax quad drive application. As for the mounting dimensions, there are guidelines that you can get from people at Twin Disc. It will depend on your bottom design and your current mechanical configuration. But the new ASD6 is intended to be a direct replacement for a sterndrive so in theory, you would use the exact same dimensions you used to place your Bravos. And forget about positive trim. This is not a sterndrive. They always run at a small angle, for example a Trimax is a fixed shaft which can be pre-positioned at anywhere between 2° and 8°. You get to play with neg trim only... As for reversing, I've never had any problems. Yes, you are running cleavers with surface drives and maybe they are not as nimble as sterndrives but the difference, if any, is very small. It's not like a boat with Arnesons is out of control when reversing...

Fred, how much power do you plan on putting in the Sutphin?

In that first pic. - whats with the exhaust going directly to the prop? Is this a new trick?
Never seen anything like it before.

bouyhunter- thats not exhaust. its an air duct that feeds the prop to help free it up when planing. if you look closely at pic #21 you can see the vent on top of the trimax drive also. defenitly interesting how the need air to get the prop to bite properly. :cool:

Hustler has been using Arnesons since the 80's. They would set up 32's with moderate HP big blocks with Arneson's for performance in the 80's.

Cuda the "wow" factor rooster tail is there with Arneson's even when cruising at slower speeds. always are crowd pleaser.

super termoli- what kind of boat is that by the way and what are the specs. looks cool, do you have any other pics.

my bro has a 39 express cat with arnesons,,, handles well around docks and in reverse runs gtrat straight too!! could be because its wide

Super Termoli/ thanks for all of the info! I still don't quite undersatnd why trim angle wouldn't be important with this setup? I have 4's on boxes and the shafts are about 1" above the bottom on a 39 Sutohen. If I run with the shafts at -2 trim and +2 trim the hull definetly takes a different set and handles differently. At 65+ the drive "torpedo" upper half is exposed. This hull has very good lift characteristics both front and rear. The mfg has tried to race with Arneson's and changed back on their 33, primarily due to handling so I am told (Basically the same bottom). I believe the trim angle played a part, especially when flying the boat and re-entry characteristics. I have a friend with the hull identical to mine with 8's and the wetted running surface is definetly greater than mine at any speed. Don't get me wrong, I am sold on the design of the various surface drives, especially on efficiency and simplicity...especially on cats. I just question the application on a v bottom if you are trying to maximize speed and handling. As far as docking goes, my friend has a counter rotating setup and in reality it probably isn't any worse than my setup. He is spining out and I in. Neither very friendly at the docks but as far as I am concerned the price to be paid. Bottom line, from my perspective, on a v if you want to run these surface type drives there are operational savings to be had, at a potential operational cost.

Too old, you're right. I believe the new ASD 6 can be run with up to 750hp but again it's more a question of torque than anything else. I mentioned around 700hp in my first post, saying that with this sort of power you should really run a SSM6 unless you like trouble. So in those cases, ASD 6 can advantageously replace the Speedmaster both in terms of cost and performance. Many people are actually running around 700hp because this is a number which can be obtained from a blown big block while keeping it reasonably reliable by running tame boost pressures. However, if you have more power, say 1000s, then you would need to step up to the ASD 8. They are much more expensive but I believe Twin Disc are working on a new version (like they did with the ASD 6) which will be simplified as a replacement for the Speedmaster and much cheaper.

Sutphen30, the Trimax is a fantastic drive, the most reliable of them all because it has the smallest number of moving parts. Its simplicity is truly beautiful and if you look at the photo, only stainless steel is in contact with water. All hydraulics and steering is inside the hull and accessible from inside for servicing. If you look at trim tabs, only the SS piston comes out while the hydraulic cylinder and lines are inside the hull as well. No leaks, no electrolysis, no galvanic corrosion... However, the big problem is that the transom needs to be configured for Trimax and that platform is necessary. It is actually very practical but it forces the manufacturers to tool up differently and modify their molds and this is why so few manufacturers are using Trimax. Even though the drive itself, once you've tooled up, is cheaper than a Bravo XR. This drive is manufactured and marketed by ZF Marine so go to www.zf-marine.com and look for trimax under their propulsion heading...

bouyhunter, glassdave is right. those are ventilation ducts which bring air to the props when the boat is accelerating from standstill. This cavitates the props or "breaks" the prop which allows you to pick RPMs up faster and thus accelerate faster. As props start to turn faster, there is a pressure-sensitive flap in the duct which is shut down as the back pressure increases. This means that the amount of air is regulated at high speeds to increase efficiency. This is one of the advantages of Trimax over Arneson in terms of performance. Arneson has the props sitting relatively deep in water at standstill with no air being channeled to them which makes it difficult to "break" the prop and accelerate fast. Then, at high speeds Arneson has props on the surface which causes too much air to be sucked in and it looses in efficiency. In other words, with Arneson, props are being well aerated when they do not necessarily need it and are starved of air when they need it, a thing Trimax has corrected and put the right way around. Another thing about that boat on the photo is the fact that it has underwater exhausts which come out under the hull and forward of the drives. This means that when the Trimax ducts are closed off at speed and drives covered by that platform, props are still aerated by exhaust gases. In addition, this provides extra transom lift and hides any smoke you may get from those diesel engines.

Finally glassdave, that boat is the new Hustler "Esprit de Soleil". It is 50' by just over 10', powered by 4 Yanmar 440hp diesels running through ZF 2-speed trannies. It is approx. 23 000lb dry and it will run close to 80 mph and accelerate to 60 in 10 seconds. It gets on plane in 3 to 4 seconds, as soon as the turbos kick in. It's a tank and it's what you need for endurance runs.

WOW . . . nice . . . very nice. feel free to post more pics of that :cool: :cool: . havent seen one of those yet. thanks for the info.

here's one pic of it running...

interior: approx. 6'10" of headroom, stand-up shower, cherry wood and ultraleather interior, corian, centralvac, flatscreen, DVD, VCR, CD changer, Sony X-plode amps, 1000W, full galley with a double burner, microwave, top loader fridge, icemaker, cedar-lined closets...

Great info. guys..
 

"Minimal radar signature thanks to the almost total absence of the rooster tail typical of other surface drives. "

This is in the advantages section of the ZF Trimax site. Why is this an advantage? Does a rooster tail block your own radar? Don't you want other boater's to "see" you better? I have very limited experience with radar (other than speeding tickets;) )

more interior with the entertainment center...

finally, this will be of greatest interest to most of us. if you're into staggered stuff, here's a double one for you. and cigwillie, Trimax is widely used by the special ops military including the Navy Seals on their fast hit-and-run and interceptor vessels and they sure do not want to be seen on any radar screens. the tragedy of trimax is the fact that manufacturers were not really receptive to it because of the re-tooling costs so it has very much become a professional bit of equipment for military, coast guard, police, customs, special forces...

This old Hustler is currently equipped with 540,s
approx 580 hp power each with #8 ASD with 16inch
drop boxes 1,33 to 1 ratio there is no steps in the hull.
there is 12 inch notch in the transom. look on page 76 in power boat magazine July.2003 issue.they did 1985 year in review the March 1985 issue The featured hustler weighing 7500 lbs did 102 mph with full trim.

That was 18 years ago When Mike Fiore's (Outerlimits)Father Desighned that hull.

I run 101 gps with full tanks of fuel.
I can also wash Bridges on the weekends.
It takes time to get use to the handling.( Stern high)
Alot of wetted surface.
Backing up sucks.
Alll in all.
You cannot even compare to stern drives.
Better fuel Economy.
More efficient propulsion System
People fall on the ground when you pull the boat on the trailer.
They handle a sick amount of Horsepower.

I would never go back to stern drives
Just my two Cents...

Here is a shot in the high 80's.

Notice the amount of wetted surface.

I have a question. There is a Formula 302 up here exactly like Cudas' boat, maybe even the same year. The Formula dealer here has been a dealer forever, so he sold the boat new.

He said, the boat will spin out if you cut the throttles too quick. He said it happened to them when the boat was new.

Now, I know the guy who owns it these days and haven't heard of any mishaps. Is this true with the Kamma, Arneson, etc setup?

I haven't tried doing that, but I haven't had anything indicate that something like that would happen. I've never heard it before either.

Yes, true. That will happen with arnesons and that is one precaution you must take. Like caveman says, you must get used to handling. It is due to things i was talking about in post #31. At speed, the props are too aerated and the transom gets light. Backing off abrubtly in a sharp turn will cause you to lose the rear end in some cases. You really have to try though, meaning maximum speed, very hard turn, drives trimmed all the way up. When I spoke to Fabio Buzzi about Arnesons, this is one argument he had against it. This does not happen with Trimax as much because the cavitation is regulated and drives are covered by that platform. However, certain things must be said. Firstly, if you really try, you can lose the rear end on a high-performance sterndrive boat just as easily, especially if it's a modern highly-ventilated stepped hull with an aggresive X dimension. Secondly, this is not really the fault of Arneson as a drive. If you know how to use it, you can go into a turn just as fast and not lose control. You just have to learn how to use it. Imagine you drive a Viper which is front-heavy and you have a certain way of handling that favorite fast curve of yours. Well, if you did exactly the same thing with a Porsche GT2, I guarantee it would bite you back and take you for a spin. Nothing wrong with that GT2 though and it's even faster than a Viper. You just have to learn to use it...

that sounds a bit too much for ASD6s. that must be full retail. but you're touching a very important point there. your sutphen is a great bottom but it has been designed with sterndrives in mind. although changing to surface drives is possible, it's a difficult process because everything is configured for sterndrives. this is why sterndrives are still so popular. it's a cultural thing. sociologists would use one of their favorite buzzwords and say that sterndrives are "embedded" in popular culture... but, if you're ordering a new boat ask the manufacturer about surface drive possibilities. Even if you're running 525s or 575s, it really is worth it and it should not cost you much more, if at all. better invest in surface drives than in a paintjob. you won't regret it and you'll never look back.

http://www.simplicity-marine.com/surfprop.htm

This is a good article explaining surface technology

fred you need 6's?

I have a question as well for surface drives -but in a single drive application. I've got a 28 foot Cigarette that I was thinking of repowering from a single HP500/Bravo One to an Arneson/Yanmar Diesel 440 HP. (What better thing to do this Winter right?)

Does anyone have any familiarity with single surface drive applications? I am hearing that the negative aspects of Arneson's (which I think would be well worth the trade offs) are greatly magnified when you only have one drive. Would greatly appreciate any input from those with experience here.