Steve Ebsen, CR, and Dave Williams, Shellsburg, are long-time friends, having met on the Cedar River (imagine that!) back in 1984. As with many guys of that generation, going fast in something with a big engine was a natural tendency. But the two opted for watercraft, rather than something with 4 wheels.
Williams’ first one was a ‘79 jet boat and when pressed for the number he has owned over the years, his answer was “a lot”! He currently owns 2 jets. The one pictured here with yellow and orange graphics, he’s had for 2 years. It’s an ‘86 Eliminator Daytona – something special that he couldn’t pass up when a friend decided to get out of the hobby. It was without an engine, but Sperry Engines bored a Chevy 454 block .045” over and stroked it ¼ ”, totaling 496 cu.in. It has aluminum heads, runs twin 850cc Quick Fuel carbs on pump gas with an R&P 671 small bore blower making north of 700 horsepower.
Ebsen bought his first jet in ‘84 and has had 4 or 5 since. His current speedster (blue/fuchsia graphics) was built in 1997 by Tom Papp Racing of Norco, CA, where a textured “race bottom”was added. This consists of 2 “tunnels” that at high speed give it more lift. Less drag from the water results in more speed. The area between the tunnels is the “keel”, while the outside areas are “sponsons”. Williams’ jet boat also has this “tunnel hull”. From CA, it was shipped to Tim Speer of Proboat Inc. in Woodstock, GA, where it was “rigged” with the jet pump, steering, gauges, fuel tank, directional levers, cables and such. Later, back home, Steve took 3 weeks to add the engine, seat mounts, engine wiring and plumbing for water and fuel. Gary Meyers of Motorhead Mfg., in Ely, IA, built the engine - a 454 Dart block, that was bored and stroked .250”, totaling 540 cubic inches. It has Brodix cylinder heads and an 871 blower from The Blower Shop of Boise, ID, making 9 lbs of boost.
After completion, Ebsen made a second trip to Georgia to have it dyno-tuned, resulting in over 900hp. He’s not sure about its top speed, but there’s a “twin” to his boat in Georgia that will do 120mph in the ¼ mile! The fuel-injected engine is set up for racing, which Steve does in Wheatland, MO, and on the Cedar. The “gas” for this engine is VP C16 racing fuel that goes for $17.50/gallon! Both of these boats are outfitted with 2 12-gallon tanks, but Ebsen’s engine draws fuel from a 5-gallon tank crucial to its use – racing. Williams’ jet runs on high octane pump gas for his pleasure cruises, and as he says, there wouldn’t be much “pleasure” in cruising the Cedar at that price for 24 gallons of racing fuel.
These low-slung jet boats are about 19’ long, not counting the 32” setback pump at the stern. The basic shell, or “hull” weighs from 400 to 600 lbs, and is made of fiberglass in a mold with balsa and Kevlar strips added. The “paint” is not paint at all, but part of the gel coat, which is the polished outer surface. In the mold, the graphics are applied first as part of the gel coat, followed by the fiberglass and reinforcing pieces. Ebsen’s hull sat in the mold for 30 days to insure that it would be absolutely straight and true. It was then removed, flipped over and the race bottom was added.
Dave and Steve fully endorse jet boats for river use as there is no propeller to hang up on ever-changing sandbars. They also cruise in 5-6” of water. At high speeds, there is very little of the boat touching the water. Steering is more responsive and precise than the more common speedboats, due to the amazing engineering of jet boats. The engine drives an “impeller” which pumps water out of the back of the boat, but yet it can back up very precisely without a reverse gear. How can this happen? Do a computer search – “how does a jet boat work?” You’ll be amazed. It’s pure genius!