Lingenfelter GMC Suburban

Lingenfelter GMC Suburban Lingenfelter GMC Suburban
Archived Specialty File

The Chevy and GMC Suburban—draft horse of the well-heeled, national car of Texas—has been around in one form or another for about half a century. But the Suburban has never been bred for speed. Even when stuffed with 7.4 liters of pushrod, cast-iron V-8 (which adds up to 454 nasty cubic inches), the Suburban is meant for hauling 150 feet of Airstream trailer, not for leaving 150 feet of smoking rubber.

There are exceptions to this rule lurk­ing around GM's technical centers. One of them is a red, rather innocent-looking Suburban. Its creators at GMC Truck call it a concept car for exploring the perfor­mance potential of their existing truck engines. An interesting rumor suggests, however, that it's also the result of inquiries from Saudi Arabian authorities looking for a Suburban that could stop both bullets and drug runners. Bullet­proofing a Suburban would mean at least a ton of extra weight in armor-plate steel and convenience-store-grade glass. Then turning a Suburban weighing nearly 9000 pounds into a speedy vehicle would be another task altogether.

GMC rang up Lingenfelter Perfor­mance Engineering for a running powertrain proposal. (John Lingenfelter, you may recall, purveys scandalously fast Corvettes that we've drooled over in past issues.) Lingenfelter was handed an other­wise stock four-wheel-drive Suburban with 3.73 axles and a beefed-up GM 4L80-E four-speed automatic transmis­sion. Out went the standard 230-horse­power 7.4-liter V-8. In its place went a marine-duty block, bored and stroked to an atmosphere-gulping 9.9 liters (that's 605 very nasty cubic inches). Feeding this monster is a long-runner intake mani­fold designed by Mercury Marine, with Lingenfelter-tweaked GM port fuel injection. It connects to a sewer-pipe­-sized intake tube, topped off by an air-box with a filter roughly the size and shape of, say, a queen-sized Sealy Pos­turepedic.

The rest of the Suburban remains unmodified, so it still has the aerody­namics of your average ranch house and weighs just about as much—a pave­ment-pounding 6289 pounds. Neither of which means anything to the horrific new engine, which affects the Suburban in strange and scary ways, ways that furrow the brows and tighten the lips of any upstanding suburbanite. Encounters with 550 horsepower and 705 pound-feet of torque will do that.

Take acceleration. If you can keep a lid on wheelspin in first gear, this Suburban in rear­-wheel-drive mode will clear the 60-mph mark in—make a note, kids—4.7 seconds. Now consider the same deal with four-wheel drive. From a standstill, the big red wagon lurches left, then right, as the axles wind up, and then it's gone, with the speedo showing 60 in 4.6 seconds.

We would have pushed on past 130 mph (28.7 seconds) if not for the BFGoodrich light-truck tires, which seemed as likely to survive a 160-mph top-speed run as would the wheels on a shopping cart. A blowout at this clip, in a truck with a center of gravity higher than the roofs of some other cars, is an experience best left to the imagination.

Then, there's that noise! Not squealing BFGoodriches, but Lingenfelter's motor, which exhales through custom-built head­ers and the Chevy 454SS sport pickup's dual-exhaust system. The unobstructed intake and exhaust produce a haunting, ris­ing wail at full throttle, the type that makes neighbors turn on lights and peek through windowshades. Ease off the throttle and the engine is a different animal, sinking to a wavering, slightly throaty, but otherwise normal idle, at 700 rpm.

A family hauler like this would make Tipper Gore naughty. We found ourselves taking detours on the way home, hoping to entice a hapless Porsche, Corvette, or Mustang GT. But with Michigan's sports cars in winter hibernation, we instead had to settle for fun of a different kind. Picture joyriding in a 550-horsepower Suburban packed with five grinning adults, their heads swaying to and fro in unison. Scan­dalous driving like this has its price at the gas pump. During its stay with us, the big truck guzzled fuel at a voracious, but not surprising, rate of 8 mpg.

If this Ferrari-muncher is just your speed, don't even think of contacting the GMC guys, because they will likely become instantly afflicted with lockjaw at the mere mention of the words "Lingenfelter" and "Suburban" in the same sentence. Instead, just buy a GMC or Chevy Suburban (about $30,000 for our test car) and drive to Lingenfelter's Indi­ana shop with another $38,000 in hand: that's $28 grand for his handiwork and another $10 grand for emissions certification, which he hasn't done yet.

At that price, Lingenfelter doesn't expect any takers. (Hey, what's Jose Canseco driving since his divorce?) Mean­while, the concept truck is still in GMC's hands. As for the Saudis, they shouldn't be surprised if they get phone calls from a few car-crazy mercenaries.

Lingenfelter Performance Engineering, 1557 Winchester Rd., Decatur, Indiana 46733; 219-724-2552