Arneson Drive Update-
Piercing the Surface Even Deeper

by Bob Brown

Featured in Powerboat Magazine 
May 1982

It hardly seems possible that 18 months have passed since the introduction of the news-making Arneson Drive to the readers of Powerboat. Although that initial demonstration was confined to an early stage prototype, there was no mistaking the invention's potential.

Between then and now, a lot of water has passed beneath Arneson-propelled boats. Those who predicted instant success as well as those who foresaw abysmal failure have been proven wrong. Today the Arneson Drive is still very much with us, an infant in comparison with other forms of propulsion but still one of the most exciting and promising innovations b brighten the industry in many years.

As is frequently the case with revolutionary products, getting to market is sometimes more trying and complicated than coming up with the original concept. After 18 months of grappling with cumbersome start-up, it now appears that the Arneson Drive is clearly on plane and picking up momentum.

The corporate twists and turns taken by the new device during that period might make good substance for an Agatha Christie mystery. In recent months, however, the plot has crystallized significantly, bringing an end to any lingering confusion about the who, what and how of the Arneson Drive.

For starters, the-Warner Gear Division of Borg Warner (the same people who built the venerable Velvet Drive marine transmissions) is now the official manufacturing and marketing entity for the product. This came about sometime ago, when creator Howard Arneson decided it would be better for an internationally established firm-to handle the major marketing effort. Warner Gear is primarily interested in capturing a share of the recreational pleasure boat market now served by traditional inboard and stern drive systems. Heading the Warner Gear effort is veteran mare industry executive Dick Schroeder, who wears the title of project manager. Assisting Schroeder with the innumerable tasks that lie ahead will be Tom Huber, who functions in a dual capacity of marketing and engineering.

Arneson himself is far from idle, having established Arneson Engineering, which is largely responsible for the continuing research and development of the unit. Arneson also has retained the right to manufacture and sell a very special manganese/bronze version of the drive (called the SP-2000) for heavy-duty commercial and military applications in addition to large diesel- and gasoline powered motor yachts which exceed the power limitations of the conventional Borg Warner drive.

The third member of the team is Gary Garbrecht, former director of High Performance for Mercury Marine. Garbrecht recently opened a company of his own called Second Effort Performance Products. It is Second Effort's duty to fulfill the needs of the high-performance/ racing enthusiast with technical expertise and special products. Actually, one of Second Effort's primary functions is to create a racing configuration of the Borg Warner production Arneson Drive by adding its own components, which are more suited to the rigors of all-out competition. Also included in this bailiwick is the job of managing the Borg Warner Arneson Drive Cougar Cat, which competes in offshore racing's Open Class I with Tony Garcia and Sammy James on board. Garbrecht, staffed by ace outboard tunnel hull racer Brett May and in collaboration with Arneson, currently is busy adding a host of new innovative products to the pure performance side of the Arneson Drive market. This complements recent updates from Borg Warner.

When the Arneson Drive was introduced, it was tested in a configuration which transmitted power from the engine to the propeller in a straight one, interrupted only by a double universal joint which allowed for up-down trim and sideways steering control. This standard and most simple melted of power transmission is still available (model 17-20 Arneson Drive by Borg Warner), but it posed a problem for certain boat builders, because the tow coupling position of the unit's internal drive line flange necessitated the engine to be positioned either too far forward b the boat or require an integral V-drive (sending a propshaft beneath the engine) setup to achieve a favorable single of attachment between engine and unit.

To eliminate this concern, Arneson Drives are now available with a drop box whereby the input shaft is boated from six to 16 inches above the output (prop) shaft. Naturally this provides much greater installation versatility, allowing the engine to be snagged dose to the transom and thus affording maximum utilization of interior cockpit space.

Of the available drop boxes, Borg Warner offers one basic unit (model 17-21) as does Second Effort (model 1600 chain drive). The difference between the two units is obvious, as the Second Effort box is considerably more husky in appearance due to its intended use for high-performance racing applications.

The more common Bag Warner 17-21 model (six-inch centerline shaft drop) is available two ways: with an internal chain and sprocket mechanism (for standard left-hand propeller rotation) or a gear drive box (for right-hand counter-rotation). The chain box consists of a Morse Hy-Vo chain and sprocket set rated to accommodate engines delivering up to 440 foot-pounds of torque. The Borg Warner counter-rotation gear system uses special helical gears which can withstand beds of up to 500 foot-pounds. Both boxes are available in three gear ratio selections: 1:1, 1.3:1 and 1.5:1.

Because a stout offshore V-8 engine is just beginning to hum at these output levels, it was obvious than ring Arneson Drive units needed a specially designed drop box. Working with Howard Arneson, Second Effort developed its model 1600 chain box, which is engineered to accept torque as high as 1400 foot-pounds. To accomplish his, a special Morse Hy-V0 chain (originally developed by Borg Warner for use in transmitting power to the wheels of an Oldsmobile Toronado back in the late 1960s and early'70s) and sprockets are used, with the output and input shafts supported by ball bearings. Virtually any amount of over or under drive gear ratio choice is available, but counter-rotation of the prop shaft must occur in the transmission (crash box) and not at the chain box. To date, the heavy duly Fly-Vo chain has proven fail-safe, with no problems during testing or b actual offshore competition. A pretty impressive testimonial to its design and construction.

Because of the variance in high-performance offshore setups and installation, Second Effort offers two chain box shaft drop options, a 16- end a 10%-inch version. Aside from the versatility this provides b boating the engine or engines forward or aft inside the hull, it also allows for some very interesting alternatives in width-wise engine placement. For instance, instead of having to stagger a pair of engines (one n front of the other) to get the propshafts as close to centerline of the hull as possible, it is now feasible to do more conventional side-by-side installation yet still achieve close together propeller thrust simply by angling the chain boxes inward.

Another interesting development incorporated into the racing version Arneson Drive created by Second Effort is the utilization of a CV (Constant Velocity) joint, replacing the traditional universal. This was definitely one area where racing experience paid off. It became clear to both Arneson and Garbrecht that the weakest link in the new drive was the universal (H-joint), which is also common to other production and racing stern drive systems. Generally speaking, a double universal joint of that type cannot be expected to accommodate in excess of 600 to 700 foot-pounds of torque for any length of time without risking failure. Because this limitation if marginal for offshore racing situations, it was decided to switch to a more durable (and more expensive) CV joint.

As most automotive enthusiast know, Constant velocity joints are frequently used by top European car manufacturers in complex transaxle systems with success. With the CV joint raw included as a standard part of each Second Effort-built Arneson Drive (model 1600), horsepower and torque levels may more than double that which conventional drive systems can withstand.

Another new feature brought about by Arneson's and Second Effort's collective brainstorming is the incorporation of a Lenco coupler between the CV joint and the drive shaft which passes through the hull. The coupler's purpose is two-fold: to provide an easy way to disconnect the drive shaft when unbolting the external unit from the transom, and to allow for a small forgiveness factor in aligning the drive and prop shafts.

Possibly the most recent innovation is the development of the Hydro Trim, an insignificant appearing piece of metal which really does a job. As originally reported in our first article about the drive, the positive trim (up) angle of the unit seemed to have only minimal effect on the ride attitude of the hull, whereas a stern drive can often bury or fly the nose of a boat depending on the amount of trim used.

This factor created some concern, especially with hulls that needed plenty of positive trim angle to achieve an efficient ride. After much experimentation Arneson settled on the relatively small delta wing-shaped attachment which bolts to the lower portion of the bottom skeg in adjustable degrees. The function of the Hydra-Trim is simple: it generates either positive or negative pressure (increasing, in effect, as speed increases), thus making an otherwise unresponsive hull respond beautifully to trim alterations (bow up or down) with a corresponding improvement in performance. Although not every boat needs it, the Hydro-Trim option certainly is a major step in the right direction for many existing hulls. And because trim control and its proper use are such important factors in determining a boat's ability to perform at its peak, Second Effort is offering a slick set of mechanical trim indicator panels and all the related hardware for easy installation. This classy package was designed arid is being manufactured by Bluewater Marine Specialties in Costa Mesa, Calif., and is adaptable to virtually every Arneson Drive.

Last on our list of things you should know about is a line of new imported four-bladed Rolla propellers called Quadrapellers, an exclusive of Second Effort's. Although the Arneson surface drive system is more forgiving in regard to propeller configuration than first expected, maximizing performance is best accomplished with a propeller designed for the specific application.

In addition to a rather generous supply of special large-blade, high rake three-bladed Arneson Drive propellers, Second Effort is soon to have a selection of the new Quadrapellers. The Quadrapeller is already a popular item with outboard tunnel hull racers in Europe because of its quick acceleration and excellent rough-water performance. On a much bigger scale (diameters ranging from 16 to 17Y2 inches and pitches from 27 to 29 inches), Rolla has taken his unique design and applied it to offshore racing and the Arneson Drive concept. Garbrecht is anxious to get these new props into competition, anticipating a definite performance advantage over conventional three-bladed cleavers. Not only should a boat be quicker and smoother with the Quadrapellers, but the likelihood of losing a blade has reportedly been virtually eliminated.

One final note worth mentioning to the true performance buff is the fact that Second Effort is offering a special extended propshaft option (standard equipped on model 1600) for the 17-20 and 17-21 model Arneson Drives by Borg Warner. The extended propshaft allows greater freedom in propeller selection, accommodating practically all racing Mercury, Kiekhaefer and Rolla props.

Events of the past 18 months have done nothing to diminish the potential of the Arneson Drive system. On all fronts, measurable progress has been made. Major boat manufacturers including Sea Ray, Wellcraft, Cobalt, SIeekCraft, Checkmate and more have seen fit to initiate test programs. Even the big-boat market (especially diesel) has responded with several successful installations (the giant SP-2000 models) now operational in 53-foot Magnums. And, of course, interest among offshore racers is growing rapidly, with a host of new Arneson equipped boats (both cats and vee bottoms) expected to compete on the 1982 national circuit. Where it all will go from here only time will tell. but don't be surprised if there's an Arneson Drive in your not-too-distant boating future.