Watch what happens when Hennessey gets their hands on a C6-gen Chevrolet Corvette ZR1.

Most of what we see nowadays is the upcoming C8 mid-engine Corvette, or the current C7 Corvette. But we rarely see anything about the previous C6 generation Corvette, and that’s just a crying shame since there’s an argument to be made that the C6 is even prettier than the C7. The C7 is all deadly edges and angry lines, while the C6 is smoother, gentler, curvier than the modern ‘Vette. It’s a car that harkens back the grand tourers of old and not the modern supercars that are far too concerned with extreme performance than comfort.

Not that the C6 was ever particularly known for its luxury comforts. But it looks like it should, and that’s the whole point.

When the C6 ZR1 was made, it came with a supercharged 6.2-L LS9 V8 engine with 638 hp and 604 lb-ft of torque. Top speed was 192 mph with weight reductions coming in the form of a carbon fiber roof, hood, fenders, front splitter, and rocker moldings. Magnetic suspension kept the ride smooth, and a polycarbonate window on the hood let you see the engine at work.

Internally, the C6 ZR1 was codenamed “Blue Devil.” This particular C6 is painted black, but it retains the blue-painted brake calipers which give the chrome wheels a blue sheen while it’s on Hennessey’s dyno.

RELATED: WATCH HENNESSEY DYNO TEST A FORD RANGER FOR NEW PROJECT

Hennessey doesn’t advertise C6 upgrades currently, so this is likely a special one-off car for a very special customer. HPE750 means it makes 750 hp at the crank, but how much does it make at the rear wheels?

Dyno testing reveals 677 wheel hp and 662 wheel lb-ft--a surprisingly efficient upgrade from Hennessey, who typically sacrifice efficiency in the name of raw power. It’s also a significant upgrade over the stock version, which produced 530 hp and 549 lb-ft at the wheels. In fact, Hennessey’s upgrade is even more efficient than stock, which is practically unheard of.

We don’t know precisely what Hennessey did to the Corvette to give it a power boost, but it’s likely the usual assortment of upgraded stainless steel headers, a high-flow catalytic converter, and maybe a tweak to the supercharger.

This C6 Corvette certainly has an exciting new lease on life, and we hope it brings it’s owners many more miles of driving enjoyment.

NEXT: WATCH HENNESSEY'S 1,000 HP CAMARO UPGRADE IN ACTION