Rocketeer: A Chevy LS-powered Quad

April 2020 • By Tony Thacker

Is it a car? Is it a moto? It’s both.

When I first spotted this little aluminum-bodied bolide I thought it was a three-wheeler because it’s called ‘Rocket 3’. However, closer inspection revealed a fourth dimension but there is method to the madness in that this is the third in a series of Rockets from artist Tim ‘Frogman’ Cotterill. Incidentally, the definition of bolide is “a large, brilliant meteor, especially one that explodes.”

“Rocket 3 combines my love of choppers, trikes, hot rods, and dragsters.” Tim Cotterill, artist and designer.

Cotterill, a British artist who immigrated to the US where he is known for his bronze frog sculptures said, “Rocket 3 combines my love of choppers, trikes, hot rods, and dragsters.” Cotterill’s first foray into the world of wheels came with Rocket 1 a somewhat conventional trike powered by an air-cooled, 1,000cc Honda CBX six-cylinder.  Rocket II, introduced in 2009, was a 1,000 hp blown, 16-plug Arruzza 426 ci Hemi made famous on Jay Leno’s Garage and YouTube.

Rocket III was a departure in that it is quad rather than trike configuration and is powered by a Chevy 6.2L E-Rod LS3 crate engine, however, it’s almost a triek as those rear tires are only 8-1/4 inches apart. Builder Randy Grubb of Blastolene fame from Grants Pass, OR, handled the build connecting the engine to a Hydra-Matic 4L65-E heavy-duty, four-speed transmission and an independent rear suspension with inboard discs from Kugel Komponents The whole lot is supported on 3 x 2-1/4-inch rails.

The pushrod-operated independent front suspension with outboard 13-inch rotors and coil-over shocks is likewise Kugel. Incidentally, that 9-inch rear diff is of the limited slip variety with a final ratio of 3.50. The rear suspension is unique in that it consists of a single, quarter-elliptic leaf spring mounted to the rear end via a single, large bearing. Under acceleration the spring flexes up “just like a big cat’s spine on the run.” Said Grubb.  The aluminum five-spoke rims are 20-inch diameter shod with Mickey Thompson 33x22 Sportsman S/R tires in the rear.

While the engineering, albeit on a short 120-inch wheelbase is somewhat conventional the body is anything but being hand-formed aluminum by Grubb.  Rather than create a wooden buck on which to form the body, Grubb built a birdcage out of ¼-inch steel rod and formed the aluminum over the top. Cotterill did the original concept that is quite organic and reminiscent of his organic sculptures from the shape of the beak to the gills behind the engine where the exhaust exits (that maybe a little hot for the feet?). According to Grubb, “The things that really made this piece good are the reverse. They’re incredibly difficult to hammer out of aluminum, but I think they really helped balance the sculpture: they diminished the volume as it moved toward the back.

Giant rear wheels and tires almost touch and the rear suspension is unique in that it consists of a single, quarter-elliptic leaf spring mounted to the rear end via a single, large bearing.

Indeed, the grill bars are remindful of some 30’s custom car grilles or even the 1937 Delahaye Franay Cabriolet and yet they blend well with the modern Plymouth Prowler headlights. Poking out of the engine cover is a double-barreled, polished aluminum, shotgun-style injector scoop. Aft of the scoop are a pair of handlebars that don’t look out of place on what is after all a quad not a car.  Made of crescent-shaped sheets of aluminum stacked Art Deco-style the right handlebar has the motorcycle style, twist-grip throttle control while the shift left is down to the left. Underneath the bars on the left are four hidden buttons for the turn signals, horn and lights.

As unusual as this build is Rocket 3’s performance, as you would imagine, is gut wrenching because of its power to weight ratio: 430 hp and just 2,000 lb for a projected zero-to 60 mph time of under four seconds and zero-to-100 in five seconds. Rocket 3 has a theoretical top speed of 200 mph but I think that unlikely. No matter, it’s a wild ride.