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Hennessey Venom GT - Road Test

Pahrump, Nevada—It’s all a bit surreal, like I’ve stumbled into the first five minutes of a Bond movie. With my right foot queuing up 12.5 psi from a pair of massive Garrett GT35R turbos, I’m shot from a cannon down the front straight…into the rotor blast of a helicopter hovering a mere 20 feet above the track surface. Pilot John Morris (also the track owner) grins through the canopy like a Cheshire Cat; videographer Jay McNally leans out of the flitting chopper like a sidecar monkey, contorting for the best shot.

And if those ominous rotors set on Journalist Frappé didn’t put me into sensory overload, the Venom GT’s raw acceleration does—a savage burst of cheek-smooshing, gut-compressing, momentarily brain-addling force, the strongest I’ve ever experienced in a road-going car. The twin pop-off valves screech like an 18-wheeler’s air brakes as I lift, then nurse the Venom GT through one of the circuit’s tight right-handers and—with the caution of a bomb squad’s eldest member—get back on the throttle. Historically, the explosive onset of power and high-cornering loads have been shown not to mix, and there’s a heart-stopping yaw moment…followed, surprisingly, by hooked-up Michelins and that addictive rush of acceleration. Must…show…restraint. This car’s already been sold, and that check won’t clear if I wad it into an $895,000 ball of vacuum-bagged carbon fiber and extruded aluminum.

Back in the pits now, and John Hennessey seems pleased at my greenish complexion and foal-like unsteadiness as I extract myself from the Venom GT’s cockpit. The lapping session here at Spring Mountain Motorsports Ranch has been as brief as it’s been exhilarating, but if seat-of-the-pants validation counts for anything, it’s clear he’s built the most formidable supercar in America, and possibly the world.

No stranger to building road cars with quadruple-digit horsepower numbers, John Hennessey took top honors back in our “Speed Kings” shootout (September 2007), where his 1100-bhp twin-turbo Viper bested even the almighty Bugatti Veyron from a standing start to 200 mph. Said Steve Millen, our driver that day: “Holy Hell! This is a wild ride. It just wants to go sideways in every gear.” Thankfully, the talented Kiwi kept it just straight enough to hit 200 in 20.3 seconds, a staggering 3.9 sec. quicker than the monster from Molsheim.

This, note, was done with a pounds-per-horsepower number of 3.1, far more acceleration-conducive than the Bugatti’s 4.5, even if the Bug does get out of the hole a lot more efficiently with its all-wheel drive. What, thought John shortly after hoisting the trophy aloft, might a car with a 2.6(!) ratio be capable of?

“I started wondering, okay, what’s next?” says Hennessey, who mulled over slightly lighter, even more powerful versions of both the Viper and Ford GT, but rejected them on grounds of being too race-car minimalist. “I was joking one day about taking a Lotus Exige and putting our Venom 1000 engine in the back of the car. And we all laughed about it; laughed about it for a couple of weeks.” But a preliminary sketch was followed up by a full set of renderings. “When they came in, I looked at the car, and by that point I’d stopped laughing. I thought, we could build this car.”

And here it is, rich silver paint glowing in the stark Nevada sunlight. At 2685 lb. with all fluids including 18.5 gal. of 93 octane, it’s about the weight of a Honda Civic, but with 8.6 times the power. Fire it up and it’s clear the guttural burble/pop at idle can only come from a V-8’s firing order. The Viper V-10’s weight, bulk and questionable future availability were all negatives, and Hennessey had become quite fond of Chevy’s 6.2-liter aluminum small-block through prior Corvette ZR1 projects. “Loved the power, loved the sound…”

Of course, this is no ordinary Chevy small-block; it has to live to 7200 rpm, make a staggering 1200 bhp and cope with off-the-charts cylinder pressures from the ceramic-bearing turbos. To this end, the LS2 block is fitted with Darton sleeves, Cometic head gaskets and CNC-ported cylinder heads, cinched together with the finest ARP fasteners. Seemingly every rotating and reciprocating bit is forged, including dished aluminum pistons, H-beam steel rods and a steel crank, the last held by billet main bearing caps. Oiling is via a dry-sump system and fueling is handled by twin Bosch in-tank pumps that feed 96 lb./hr injectors. The engine bolts up to a Ricardo 6-speed manual transaxle that’s identical to a Ford GT’s, ratios and all, that puts power to the massive 335-section Michelins through a Quaife limited-slip diff.

Raise the Venom GT’s rear-hinged engine cover (lined with gold foil, incidentally) and it’s clear that Hennessey sweats not only the power but the appearance. Aft of the seats, the Exige’s aluminum monocoque architecture ceases and Venom GT begins with a stout chrome-moly steel subframe, triangulated by two beautifully gusseted V-shape braces that bolt up to the rear hoop of the considerable rollcage structure. There’s tidy symmetry in the twin water-to-air charge coolers, the blow-off valves, the wastegates, turbos and conical air filters. And the muscle-bound central exhaust, with 3.5-in. dual tips poking through the bodywork’s mesh, has a beautiful golden cast…it’s sandblasted stainless steel that takes on its distinctive hue when heat is applied.

Inside, the Exige’s basic interior is intact, but embellished for slightly greater comfort and style. There’s lots of black diamond-stitched Alcantara, smooth leather and a carbon-fiber sheath over the 2-dial instrument cluster. Bits of exposed aluminum remain, completely fitting here. And the stout rollcage is evident, though its tubes are wrapped in the same diamond-tuft microfiber that lines the seats, door panels and dash top. My helmeted head fits neatly in a triangular recess of the X-brace connecting the front and rear hoops…tight, but just enough room. The view straight back? Shiny blow-off valves, black mesh and ducting, but at least the outside mirrors are large and well-placed.

Outside? It’s an Exige with a Gold’s Gym membership, ripped muscle with that Porsche 917 long-tail look from its stretched wheelbase (at 110.2 in., it’s a substantial 19.7 in. longer than that of its donor chassis) and massive rear fenders that swell around the rear Michelins. The Exige’s visage is maintained with Lotus headlights and sharply peaked fenders, but broadened and underscored (literally) with a thick splitter that incorporates twin underbody venturis farther back. At the rear, the taillights seem to float in the mesh grille, and a generously straked underbody diffuser extends well beneath the engine. Combined with the rear wing (hydraulically adjustable for height and angle of attack, yet fixed at this stage of development), Hennessey estimates these measures will generate downforce somewhere in the vicinity of 1200 lb. at 150 mph, according to CFD simulations.

Hennessey will be the first to admit that there’s much more development to be done. Although he and chassis guru John Heinricy (yes, that Heinricy, the 39-year GM performance veteran with five national SCCA T1 championships, assistant chief engineer for the C4 & C5 Corvettes, etc.) have created a monster in the best sense, another year of optimizing the Venom GT awaits before production hits full stride. For instance, the active KW suspension (an electrohydraulic system can raise the car by 2.4 in.) and the rear wing will be programmed to work together to achieve downforce, reduce drag or produce a happy medium, depending on the situation. Motec engine management will replace the current reflashed GM ECU and HKS boost controller, and a traction-control system that adjusts throttle position and boost level ought to tame the Jekyll/Hyde power hit. Plans include test sessions at the Nürburgring in the summer of 2011, with Hennessey hoping to ultimately break the 7-minute barrier.

I’m reunited with the Venom one last time at our usual El Toro test venue, where I can flog it around for additional impressions. The lightness of the steering, clutch and the delicacy of the shift action seem incongruous with the massive power, and even with roughly 60 percent of the weight over the rear axle, the 235-mm front Michelins—dwarfed by the rear tires—feel overtaxed in hard cornering. A fix is in the works, as 255s on 1-in.-wider wheels will be fitted on future builds.

But let’s celebrate what this car does best, with a mile of runway before me. Again, hard through the gears, turbos at full whistle, the Venom inhaling the horizon in one last tunnel-vision orgy of speed. The pavement seams are no longer felt separately, now a continuous drum roll of vibration and intensity. The tach reads 6100 in 4th, or about 165 mph, before exhausting available runway and nerve. Just getting started…a shame.

It’s then hard on the carbon-ceramic 6-piston Brembos, then a cool-down crawl to the trailer. After this thrill ride, a theoretical top speed of 272 mph seems entirely possible. And Hennessey has a history of delivering on crazy promises.

Twelve hundred horsepower. Less than 2700 pounds. “Do the math,” says Hennessey, “and the outcome is basically a car that’s thrilling and borderline scary to drive sometimes.” Here’s to being a little scared.

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