2010 Ford Shelby GT500 vs. 2010 Hennessey Performance HPE550 Camaro

These are the heavy hitters. The big dogs. They're not playmakers or finesse artists and they don't dish out assists. If the 2010 Ford Shelby GT500 is Dick Butkus snuffing out a Jim Brown thrust up the middle, then the 2010 Hennessey Performance Engineering Chevy Camaro SS HPE550 is Lawrence Taylor with radar lock on Joe Theismann's right leg. And it's not just that they're powerful and merciless, but intentionally provocative and intimidating, too. On looks alone, either of these cars is enough to make the drivers of other machines cower like a three-legged Labradoodle.

They are, of course, muscle cars in the rawest, most vicious sense of the term. And they're quicker, faster, meaner and flat nastier than anything built back when Ol' Shel and Don Yenko were just guys. And not by a little bit either.

But which is the better beast? To find out, we drove these two all-Americans on the street, at our test track and on the Dynojet chassis dyno at MD Automotive in Westminster, California. Then we did some big smoky burnouts just to piss off the Sierra Club. By the time we were through, Greenpeace had threatened to blockade the Inside Line garage and the Obama administration was seriously considering a unilateral deployment of the fun police. Didn't matter. By then the tires were shot and we had our winner.

Overwhelming
Both the GT500's and HPE550's power plants are familiar concoctions. The GT500's engine is essentially the same 5.4-liter DOHC, 32-valve iron-block beast used in the 2007 Shelby GT500. It's still topped by an intercooled, Eaton-made, Roots-type supercharger thumping up to 9 pounds of boost. Recalibration and the inclusion of the cold-air induction system from last year's GT500KR have, however, boosted output from the original 500 horsepower to 540. Despite drinking California 91-octane pump gas, the 2010 Ford Shelby GT500 made big numbers on the chassis dynamometer. We measured 511 hp at the rear wheels.

To create the HPE550, Hennessey conspired with Magnusson Products and adapted one of that company's Eaton-based MP2300 Roots-type superchargers to the Camaro SS's 6.2-liter single-cam 16-valve all-aluminum LS3 V8. It's similar to the system Magnusson had earlier developed for the Camaro's brother, the Pontiac G8 GT sedan and includes interesting elements like a small driveshaft that runs along the side of the supercharger case to drive the blower, but no intercooler.

Hennessey added its own cold-air intake and bolted on a Corsa cat-back exhaust before tweaking the engine control computer's fuel map for maximum thrust (but the heads never came off the LS3 and all the internal parts are as GM assembled them). Hennessey claims 562 hp is the result — and we measured a gob-smacking 559 hp on the chassis dyno, although it was running on an unspecified witch's brew of high-octane fuels during the test.

Those are numbers. And they don't tell much of the story.

Walloped
The 2010 Hennessey Performance HPE550 Camaro starts with a sledgehammer thump to your sternum. Even at idle there's menace in this car's growl; it's up to no good and it's inviting you to go along with its dastardly scheme. It's evil, but the fun kind of evil.

In contrast, the 2010 Ford Shelby GT500 seems tame on ignition. After all, it's a product of the Ford Motor Company and it complies with every unreasonable noise law on the books. But this is hardly a timid car; it sounds flat wonderful, and happens to bite more viciously than it barks.

Both cars are equipped with versions of the Tremec TR-6060 six-speed manual transmission. There are some variations in the gearing (6th in the Camaro is a deep 0.57:1 overdrive; the GT500 is even deeper at 0.50:1), but finding 1st in either car takes a determined shove.

Slammed
Drop the HPE550's clutch and the engine slams to its 6,600-rpm redline as if it's just been head-butted by a rocket-propelled goat. The throttle is essentially an on/off switch; there's only a scant couple of inches of pedal travel before the throttle is wide open. Modulation? You want a nice progressive throttle? Hennessey Performance Engineering isn't in that business.

Fortunately the HPE550 wears massive 315-millimeter-wide rear Pirelli P Zero tires that turn most of that insane engine speed into forward thrust. This car accelerates hysterically; there's so much momentum that you have to fight the G-forces to shift gears. And the sound is crushing. This is full-immersion acceleration — you could drown in the HPE550's sensory overload.

The GT500's rear Goodyear F1 Supercar tires are "only" 285mm wide and it takes more skill to launch the Ford perfectly. Fortunately, Ford's SVT division has actually built some of that into the GT500's throttle. This isn't an engine on a runaway gallop to its redline; the first inches of pedal travel ease into the thrust gradually.

Bottom line, however, is that the 2010 Hennessey Performance HPE550 Camaro is quicker. Still drinking that high-octane concoction, the Hennessey HPE550 stomped to 60 in only 4.3 seconds (4.0 ticks with 1 foot of rollout like on a drag strip) while the Shelby GT500 (on California 91 octane) took 4.6 seconds (that's 4.3 seconds with the rollout) to do the same trick. The quarter-mile screams by in 12.1 seconds at 120.1 mph in the Hennessey Camaro and 12.5 seconds at 115.3 mph in the Mustang.

Sure, the Hennessey car bounces along its rev limiter during the run, while the GT500's engine is always composed. But quicker is, fundamentally and unalterably, quicker. Plus, the Mustang's shift quality just isn't up to the Camaro's — despite the fact that they run essentially the same transmission. Then again, the Camaro suffers from elephantitis of the shift knob. Feels like a leather-wrapped gourd. No thanks. We'll take the classic hard white ball offered by the Shelby.

Stuck
Acceleration is one thing, but living with a car is something else. And sometimes that involves going around corners.

The HPE550's humongous 275/40R20 front tires are so big that they deaden the steering and there's no real payoff in instantaneous turn-in. Combine that with Hennessey's suspension package, which features springs that are too stiff and shocks that are under-damped, and the result is a car that never feels settled or comfortable over any surface. And that's despite the fact that the Camaro has a multilink independent rear suspension.

Sure it looks bitchin' lowered like it is, but it doesn't really work. The car's ride is ruined and we were unable to find any handling improvement over stock. At our test track the HPE550's 0.87g performance on the skid pad and 68.7-mph slalom run are no better than what we've recorded in a regular Camaro SS.

Meanwhile, the 2010 Ford Shelby GT500 handles shockingly well — particularly in light of what a pig the previous GT500 was. Always composed and always comfortable with extremely well-controlled ride motions, the 2010 GT500 ripped around the skid pad at 0.93g and bounded through the slalom at 69.3 mph. It's an astonishing performance from a car with a solid rear axle — though it would be better if the front 255/40R19 Goodyears were more communicative.

But even those numbers understate how much easier the GT500 is to live with. The chopped-roof appearance of the Camaro means bunker-slit visibility, while the Mustang's loftier greenhouse allows the driver to actually see where he's going and where he's been. That alone makes it easier to drive the GT500 harder than the larger and heavier Camaro.

Both Ford and Chevy chose Brembo as the brake supplier for the GT500 and Camaro SS. The HPE550 stopped from 60 in 109 feet while the GT500 took 112. Not bad considering that neither exhibited much fade during repeated stops, but cars with this much thrust and such lofty price tags should be stopping from 60 mph in 105 feet or less.

Living Large
Ford did a shockingly thorough job of improving the whole Mustang lineup for 2010. What seems at first to be a minor midcycle update of the 2005 car has, in fact, resulted in a much better-driving, much easier-to-live-with machine across the range. But no Mustang is more improved than the GT500.

The wizardry performed on the 2010 Ford Shelby GT500's suspension is simply amazing. That's still a big iron lump of an engine up front, but somehow the suspension tuning (mostly) compensates for that weight. Pressed hard on our favorite mountain road, the GT500 will still plow its nose, but nowhere near as drastically as it did before. And with some precise throttle modulation (and the traction control system turned off), that understeer can be balanced with additional power. Could the 2010 GT500 be better? Sure. But as it stands, this is the best Mustang ever. And it's not even close.

The 2010 Hennessey Performance HPE550 Camaro is a hot rod; more severely compromised in the pursuit of performance than any OEM would dare unleash on the public. Given some time, Hennessey should clear up the suspension issues and fine-tune the engine so it's easier to manage. But it's also a 2010 Camaro, and while there are advantages to that, there are disadvantages, too. You know, like the restricted visibility and a shallow trunk that's accessed by what amounts to a mail slot. This car's performance is almost religiously transcendent, but it's performance that is best appreciated by true believers willing to put up with hassles in exchange.

Everyone here loves power. But all of us would give up the Hennessey's rocketry in exchange for the GT500's much better handling, easygoing livability and overall civility.

Ka-Ching!
Done up in Grabber Blue with race stripes across the seats and on the shift knob and wearing 19-inch wheels, the 2010 Ford Shelby GT500 looks good and thoroughly American. No Mustang looks like a $50,000 car, but this one comes closest. As it should, since it is a $50,000 car.

Wearing Yenko drag and lowered over its 20-inch wheels, the 2010 Hennessey Performance HPE550 Camaro is both more dramatic and more sinister-looking. It attracts attention the way tall bridges attract suicide attempts. But at $62,500 through the doors of Hennessey Performance in Houston, it's dang expensive. And as intoxicatingly explosive as its performance is, the regular Camaro SS would be easier to live with.

So it's the GT500 that gets the love here, even though the HPE550's thrust has a grip on our gonads. Brute force, it seems, is best when served in a more civilized container.

The manufacturers provided Edmunds these vehicles for the purposes of evaluation.