Hennessey-tuned Ford GT does a 235.1-mph Texas two-step

A few times a year, some of the fastest and most powerful cars meet in Texas for an adrenaline-filled weekend of top-speed runs called the Texas Mile. The high-performance machines have one mile of arrow-straight runway to get the highest top speed at the one-mile marker.

It was the right mix of conditions for Mark Heidaker and Sean Kennedy, who drove their twin-turbocharged Ford GT to a top speed of 235.1 mph down the runway into a decent headwind of 20 mph.

Lucky for us, the Hennessy-built Ford GT was equipped with a VBox, which provides info, audio and video of the session-winning run.

To turn the already muscled Ford GT into the flame-throwing Hennessy GT1500, the boys in Texas threw on two 67-mm ball-bearing turbos, custom intake and exhaust, twin waste gates and twin blow-off valves. They upgraded the fuel system with new lines, pump, fuel rails and injectors.

The stock 5.4-liter V8 was improved with a custom forged crankshaft, forged aluminum pistons, forged steel rods and balanced rotating assembly. Four custom-ground camshafts were added with upgraded valves and valve springs.

The GT gets an upgraded clutch and flywheel, an adjustable boost controller, custom tuning and ported factory cylinder heads. Hennessey claims the total power of the tune is a stampede of 1500 horses at the flywheel; 1290 hp at the rear wheels.

The upgrades cost a cool $105,000 and take about 4-6 months to install. The total cost as tested is $142,000, which isn't too bad for a world-beating domestic supercar. The upgrades do requires a donor vehicle, and that's not included in the price.

Enjoy the two videos. One is the top run of 235.1 mph, and the other has all of the VBox information on a run of 232 mph.

By Jake Lingeman