We Twin-Turbo’d Leno’s V12 Hemi

“It’s March 9th, 2004 I’m sitting in the hospital room holding my newborn grandson,” recalls Gale Banks in his latest video. “My phone rings and it’s Jay Leno. He says, ‘What’s his name?’ I say, ‘Bronson.”’ He says, ‘Cool name. I want to turbo the tank car!’ …all in one sentence. I said yes, and he brought us the car.”

Designed for Korean War-era tanks, the 30-liter air-cooled Continental V12 Hemi engine was good for 810 horsepower on 80-octane fuel. The tank it was designed to move weighed 48.6 tons. The power to weight ratio was 17.6 hp per ton. Jay’s car is quite a bit lighter, weighing in at only 5 tons, of which 2,300 pounds is engine.

“Jay asked me to double the horsepower and make it reliable,” Gale says with a chuckle. “So, we built a Banks twin-turbo system using Garrett TE0-691s, famous for their use on Indy cars. We engineered intake manifolds with expansion joints because the aluminum engine would grow so much. We fabricated exhaust manifolds and straight-pipe exhausts. Yes, it sounds bad-ass.” 

Gale and the team replaced the carburetors with Bosch fuel injection designed for V12 Formula 1 engines and fuel injectors were fed by a pair of Banks billet fuel rails. It was all designed to look retro.

“When we were done,”  says Gale, “it produced 1,600 horsepower at 2800 RPM. And we doubled the fuel economy which was easy because the tank guzzled 2.3 gallons per mile.”