Gale Banks turbocharged engines completely dominated the 1978 edition of the New Zealand Citizen Jet Boat Marathon by powering boats that finished 1st, 2nd, 3rd and 5th. Grabbing the win was Reg Benton of New Zealand making this the second consecutive marathon win for him in as many months. His margin of victory in the grueling 1000 kilometer event was a staggering one full hour. Powering Benton’s jet boat was a 454 CID, twin turbocharged Gale Banks Chevrolet engine. Finishing behind Benton, the top five were as follows: 2nd, Howard Smith with a 350 CID Gale Banks turbo engine; 3rd, Alan Johnson with a 454 CID Gale Banks turbo engine; 4th, Max MacKenzie with a 496 normally aspirated engine and 5th, Selwyn Paynter with a 350 CID Gale Banks turbo engine. Every boat in the top five used a Hamilton jet.
The New Zealand Marathon was the third major international event that had been won by a Gale Banks turbocharged engine that year. Benton’s wins in Canada and New Zealand accounted for two and John Westland won his class in the recent Rio Balsas race in Mexico also using a Banks engine. “Since this trio of races constitutes all of the recognized international river racing marathons”, said Gale Banks, “it seems reasonably safe to say that our turbocharged engines are the World Champions of river marathon racing”.
The river racing series is the most punishing type of endurance racing imaginable because the 900 hp Banks turbocharged marine engines are constantly shock loaded and subjected to 7-8g impact loads that can rip the flywheel right off the crankshaft. The engines also have to have a very broad power band so they can idle down to negotiate shallow waters and then blast off to full power.