Externally, the is indistinguishable from . But under its skin lives a brand-new, 6.2-liter, 411-hp V-8. We didn't desert race it, but we did cover it in two inches of mud.

Spring in Michigan can be very hard to live with — it's the kind of weather that turns a man's thoughts to cheap beach houses in South America. It had been pissing a cold, hateful rain for three days in Detroit. This would normally be a downer on a first drive, especially one focused on a high-performance product from Ford's SVT division.

The product is , the second of what so far will be three vehicle versions (the third being ). This made it a brilliant day for a drive.

When the Raptor debuted two years ago, its brash courting of danger was a bit shocking — how had Ford's lawyers let it get away with designing a truck whose advertisements almost exclusively pictured it in mid-air? This — a desert-focused repli-racer — was a whole new avenue of performance, and the truck didn't disappoint. The only trouble was the powerplant.

When the 5.4-liter Triton V-8 debuted in 1997 with the newly jelly-beaned F-150, it was hailed for its power delivery and fuel-economy improvements over the outgoing 5.0-liter. That was 14 years ago, however, and the 320 hp and 390 lb-ft the engine developed in the Raptor just left the truck feeling a little flat.

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That all changes right now. Let's just come out and say it: The Raptor fitted with a 6.2 is the equivalent of shooting bottle rockets at a gas station: It's powerful, angry, malicious, tacky, and on the fun scale, just this side of owning a surface-to-air-rocket launcher. A faster Mustang? That's great. A Taurus SHO? Chubby but nice. But the 6.2 Raptor is different — it's meaner, way more stupid, and hell of a lot more dangerous to pilot.

The 6.2-liter eight is an all-new design with a cast-iron block and aluminum heads, two valves per cylinder, a cast-iron crank, and cast aluminum pistons. It's got two spark plugs per cylinder and cranks out a healthy 411-hp and 430 lb-ft of torque. It's backed by a six-speed automatic transmission.

Recall now the rain we mentioned earlier. We tested this pissed-off F-150 at Ford's Romeo proving ground with dirt so soggy it wiggled like Jell-O. Yeah, we got a bit muddy. Switch the transfer case to 4-High, engage the electronic rear locking differential, push the "off-road mode" button to deliver a more aggressive shifting schedule, and push the Advance Trac button once to enter sport mode. After that, floor the accelerator and enjoy four roostertails of mud erupting along a graceful flight path. Where the 5.4-liter Raptor would understeer in low-traction situations, lacking the grunt to easily move the rear end around, the 6.2 will turn a happy pirouette with the right application of loud pedal. It also sounds damn good, a throaty and urgent exhaust note tumbling out the rear pipes.

With traction control fully engaged, the truck clamps down hard on any chassis excitement, killing engine power and locking things down. In Sport mode, however, things can get really, really crazy. The system opens up the yaw limit for righteous oversteer and significantly loosens the ABS threshold. This is one of the few instances where a vehicle performs better in sport mode than with the nanny systems fully defeated. With all the nannies killed it's really easy to overcook a gravel apex or find yourself facing the wrong way against a one-way tree.

Everything we loved about the '10 Raptor is still there: The huge 2.5-inch Fox Racing shocks and beefy SVT control arms work in concert to soak up even the nastiest whoops and drop-offs, and they provide buttery-soft landings once you air down the tires. With a long-travel suspension delivering 12.1 inches of travel up front and 11.2 in the rear, you'd expect body roll to be excessive and sloppy, but in quick transitions, the truck simply rolls to the side and plants firmly.

The thing we found most surprising, however, was the Raptor's talent on tight forest trails. Normally, rolling a full-size truck through slippery, tree-packed trails is not a question of if you're going to bash something, but when. The Raptor rides on a relatively short 133-inch wheelbase, and despite the additional seven inches of width over a standard F-150, it doesn't feel overwhelming in tight spots. Sight lines are good, and the huge mirrors can be adjusted to spot the rear wheels. Even though the Raptor rides on 35-inch BF Goodrich tires, its engineers managed to come up with an impressively tight turning radius.

The trouble with the Raptor is that there's nothing to compare it with short of a full Baja race rig. By mid-July, Ford should be dropping its Raptor Crew Cab, which is promised to have another 12 inches of wheelbase, real rear doors, and more back-seat legroom, closing off the only possible avenue for complaint. Well, that and the fact that the steps very effectively act as a mud shelf. The 6.2.-liter mill brings along a $3,000 premium, but we suspect the vast majority of Raptor buyers will check that box going forward.

They'll be getting their money's worth. The 2010 Raptor is a far more satisfying machine with this new engine, and easily the most entertaining product you can be in when the pavement ends.