Modifying Toyota Supra engines is all fun and and good, but that gets done a lot. A tuning shop in Minnesota refreshingly didn’t go that typical route, instead combining turbocharged six-cylinder engines pulled from two Supras and combining them into a V12.
Don Groff at Nth Moto had the idea to meld the two inline-six engines he got from the Supras together and he’s been working on it for eight years, with an admittedly weird end goal: He said in an interview with Road & Track the idea was to take the two engines and make them into a 5.0-liter V12 with a target of 800 horsepower.
He’s using a pair of 1JZ engines from the Japanese MKIII Supra for the job. That 2.5-liter inline six engine was never sold in America on that Supra, but it was used on a litany of Japanese Toyotas, and remains a popular swap and modification option across the world today. (The slightly later and more famous 2JZ inline six had 3.0 liters of displacement.)
People modify Supra motors to well over 1,000 HP all the time, so 800 HP for such a strange and involved project seems a little modest. Even Groff said the whole project makes no sense.
But Groff, 71, told Road & Track there’s no reason to tune it to 1,000 horsepower “other than talk.” He said you “can’t hook it up and you can’t drive it anywhere near safe” at that number, and that he thought 800 HP was a good target to keep the engine running well and the parts alive.
Weird goal or not, this thing sure is turning out to be beautiful. Here’s a clip Groff posted of his new V12 on YouTube, which sounds rather lovely:
Groff told Road & Track it was “pure, blind, dumb luck” that made this idea to weld the two six-cylinder lines into a V12 an actual success, and that he didn’t know any of the excerpt below before buying the motors. From Road & Track:
So without doing much in the way of investigation or measurement, Groff picked up twin 1JZ engines yanked from early-’90s Toyota Supras, cut the blocks just above the oil pan gasket surface, and scratch-built a new crankcase out of TIG-welded 3/4-inch steel. “Where I got lucky is the head bolt pattern is symmetrical,” Groff tells me. “You can flip the head end-for-end. There are 13 oil drain-back holes in the block. Those are what I used to bolt the cylinders to the crankcase.
It also isn’t stuck with the norm, because our new hero Don Groff spent nearly a decade weaving two Supra engines together for no reason other than the fact that he wanted to do it. He told Road & Track he’ll probably just use it to drive around town and in the neighborhood, because he didn’t build the engine to the specs of any racing organization.
That, right there, is the kind of life we should all aspire to live.