Hummer H1 - Duramax Hummer

If you saw this vehicle rolling down the streets, you might mistake it for an old, military-spec HUMVEE, and not much else. But you'd be wrong, because it's owned by Joe Komaromi of Pacific Performance Engineering. Joe's plan was to build the ultimate on- and off-road vehicle, and we'd have to say that he pretty much hit the nail on the head with this one. For starters, the wheezing, hot-running 140hp 6.2L diesel was yanked in favor of an '04 6.6L Duramax. And who could blame Joe for wanting more power? He reports the new engine makes more than triple the power of the original engine, is more efficient, and more reliable. In fact, it's powerful enough to send the Hummer down the dragstrip in 12.8 seconds at 101 mph, and Joe also claims it's economical enough to let the 5,800-pound Hummer achieve 20 mpg on the highway. But wait, there's more.

With more than enough power to tackle dunes and hills, Joe turned his focus toward the rest of the drivetrain. An Allison 1000 transmission got the nod for its torque-handling capability and overdrive gear, and it's bolted to an NV263 push-button transfer case out of a GMC 3500. The Hummer's independent front and rear axles are known for breaking halfshafts, so a set of 12,100-GVW units were swapped in from a HUMVEE ambulance. To provide traction, 37x12.50R17 Baja T/A rubber from BFGoodrich mounted on anodized Hummer H2 wheels rounds out the combination.

What really sets Joe's Hummer apart from other swaps is that it's not simply an engine swap, it's a vehicle that has had its entire drivetrain, electrical, and mechanical systems upgraded. It can tow thanks to a Class IV hitch and an electronic brake controller, and it can race down the dragstrip, drive down the street, and hit all the dirt roads between those two places. We bet Joe would even sled pull with it if we challenged him to.

Of course, building a vehicle this noticeable has led to many asking the inevitable question: "How much is in it?" Well, unfortunately, one-off vehicles don’t come cheap, as there's an estimated $150,000 in parts and labor in the H1. When we went for a ride, it became clear how well spent that money was as Joe shifted from Second to Third, getting sideways and boiling the tires at 50 mph. "One time at the dragstrip, I pulled up next to a guy in a street-tired ZO6 Corvette," said Joe. "Never in a million years did the Corvette owner expect to get beat by a 3-ton military vehicle, but he was," said Joe, smiling.