
Cole and the Berserker Duramax rip the LACR starting line on their way to a 12-second grin.
By tradition, we've held diesel-powered vehicles with the same high regard as hog jowls, tripe, and a big spoonful of calf's foot jelly. Even turbocharged editions didn't raise so much as a blip on our hot-stuff radar screen, so when Steve Cole, program-tuner par excellence and owner of TTS Power Systems, dangled the keys to an '01 2500HD Duramax cow (perhaps water buffalo would make a better analogy), we had to stifle the urge to smile. C'mon Cole, you're talking about a "rush" that's all over at 3,200 rpm. All the same, we knew his penchant for the practical joke ... and it was difficult to deny those hundred-foot-long black stripes on the tarmac in front of his building.
Not long afterward, we huddled in stark amazement at the animalistic behavior of his 6,500-pound rattler. In it, the concept of torque becomes a living, breathing entity, a huge cube of energy crushing through the envelope of air vainly trying to hold it back like some monster battering ram. Watch that BMW disappear in the rearview amid yards and yards of rubber and smoke. Yikes, this thing was fun! Winded and with bumping pulse, we returned to the cow pen. Cole was smiling. We braced ourselves for his I-told-you-so onslaught.
Two weeks later, we're back at the cow pen. Cole says, "Try it now. And watch out, you'll have to drive it when it hits Second gear." Huh? We slapped the loud pedal. OK so far. The Allison five-speed jumped to Second and the tires fried beyond belief, eerily silent in their complete and immediate loss of traction. The back end marched heavily to the right. We cranked in a bunch of opposite lock to straighten it out. Out the rearview, the skinny stock rubber silently continued to paint stripes of pain.
Cole explained that he called this program Extreme, and that he was ambivalent about letting it loose on the public. "It puts 890 lb-ft and >> 520 hp at the wheels. It's nuts, I know, but some people won't be satisfied with the regular programs if they know this one exists. They'll have to have it."

Already formidable in its own right, the 403ci Duramax in Cole's Silverado 2500HD is factory-rated at 520 lb-ft of torque at 1,800 rpm and 300 hp at 3,250 rpm. The engine was untouched. The computer was tweaked heavily.
So we've let the cow out of the bag, as it were. At this writing, Cole is still undecided about the availability of the killer package, but he's currently providing a programmer with three distinct performance modes as determined by his Power Loader: economy, tow, and race. The stock 6.6L (403ci) Duramax produces 448 lb-ft and 245 hp at the wheels. The economy hop-up kit provides an additional 80 lb-ft and 46 hp. When it's in tow mode, expect an overall infusion of 207.8 lb-ft and 90.2 hp. With the race program workin', the Duramax heaps 318.2 lb-ft and 135.7 hp on top of the baseline configuration. Output is measured at the drive wheels. To get the killer package (which is not represented in the dyno chart), you'll have to sign a waiver excusing TTS from the driveline damage that will most likely occur.
To guard against the inevitable, Cole has partnered with TransGo to develop a shift kit for the five-speed Allison automatic to firm up the gear changes in conjunction with healthier clutch discs and stronger springs. Accordingly, Cole reworks the stock torque converter and furnace-braises the vanes (there's other stuff, but he declined comment). The main area of attention is the side of the converter that faces the engine, or the clutch side of the converter. The stock unit features raised bosses that bolt to the flexplate. Under the extreme duress of Cole Power, these bosses are pulled off-center and distort the surface that the clutches apply to. The result is a grossly uneven clutch application. Slippage that occurs is enough to wipe out the transmission. TTS affixes a strengthening ring to the flywheel side of the converter to hold the clutch face true and spread the applying force evenly over the entire surface.
Aside from a TTS 4-inch-diameter stainless steel exhaust system, the engine is untouched; virtually all of its formidable largesse is the result of Cole's mapping of the electronic engine controller as induced via his Power Loader. Unlike the competition's stand-alone software, which requires stopping the engine and loading separate programs, his Power >> Loader (via a three-way switch mounted below the steering wheel within easy reach of the driver) serves up the individual programs on the fly. Though the stock fuel system provides 25,000 psi of pressure, Cole installed an electric pump to pull the go-juice from the fuel tank to the motor with a maximum of 4 psi. The injectors are Duramax original equipment and quite sufficient to accommodate the 30 psi of positive manifold pressure. He warns that the Allison will work fine with the economy and tow tune-ups, but anything beyond that absolutely requires the transmission upgrade and the bulletproof torque converter.

Cole did real-world testing on a hilly route pulling north out of the L.A. basin; he loaded the bed to the hilt and dragged a car and trailer behind it. He reports that the ability of the package to handle the load (25,000-pound gross vehicle weight) while accelerating up an 8 percent grade at 70 mph with no slipping, no codes displayed, and no clutch damage was beyond his expectations. We weren't part of the baggage, so we'll have to take his word for it. We did see the cow rumple up the dragstrip starting line, though. To prepare for this phase, Cole wedged the axle pads to put the pinion at a 2-degree angle and installed reinforced spring shackles to keep the leaves from winding up. He also applied 10-inch-wide Mickey Thompson 12.50x28 ET Streets to the stock 7-inch aluminum wheels and pinned them to the tire bead with screws.
Running through a 3.10:1 low gear and a 3.73:1 axle ratio, the monster grunt wanted to vaporize the Mickeys, which were set at 16 psi. But they wadded up like they're supposed to, and he was able to manage 60-foot times in the low 1.80-second range. He left the line a little above idle generating about 3 psi of boost and clipped the Los Angeles County Raceway (LACR) clocks with a 12.78 at >> 106.098 (uncorrected). Applying the sea-level conversion factor, this becomes 12.36 at 109.67.
So what price glory? Not much at all, really, when you figure the truck cost more than $30K. The killer converter is $1,050, the TransGo kit is $453, the exhaust system is $535, and the three-position Power Loader is $895. For obvious reasons, TTS extends no warranty on the transmission kit, but the converter is good for a one-year guarantee. It'll be completely worth it the first time you blow that snoid in the Z06 Corvette back to last week.