Let’s talk about horsepower for a minute. Most of you are familiar with the 6th gen ZL1 Camaro, C7 Corvette Z06, and Cadillac CTS-V and their monster LT4 powerplants. For those of you not in the loop, the LT4 is a 6.2L, Eaton 1.7L-supercharged, direct injection beast that makes 640-650 horsepower at 6,400 rpm and 630-650 lb-ft of torque at 3,600 rpm, depending upon application. Everything about this engine is built for abuse, from its 1538MV forged steel crankshaft, I-beam connecting rods, to its forged pistons. The engineers at GM knew their customers would be putting these engines to the test, day in and day out and assembled them with the best technology available. And gave them a warranty.
Not only are the engines practically bulletproof, the rest of the driveline is absolutely nothing to sneeze at. Each of the aforementioned cars available with the LT4 could be equipped with a standard 6-speed transmission. However, the ZL1 Camaro allows you to check the box for the mega rad 10-speed automatic 10L90 transmission. For drag racing and straight line performance, the 10-speed is the supreme choice. First gear is super low and makes for spectacular 60-foot times, the shifts are fast, and the engine easily stays within its powerband during a pass. And the sounds a 10L90-equipped car makes going down the track will have you thinking a superbike just made a hyper-shifting run down the strip..
So what does all of this jibber-jabber have to do with trucks, you ask? Sit tight, and I’ll tell you the story of Justin Keith’s killer, teal ‘93 Silverado. You see, Justin loves his OBS trucks. Currently in his stable, you’ll find a few mint, low mile examples, including a 7,000-mile black 454SS, a ‘93 Indy pace truck, and a low mile white paw-paw truck, amongst other late model hot rods. He’s no stranger to drag racing and bad ass cars, either. He’s half of the duo responsible for creating and hosting the wildly popular Street Car Takeover events across the country, and he also owns a very busy performance shop in Kansas City called Killer Performance. If that’s not enough, Justin is the owner of a well-known Crush orange record-holding ‘19 ZL1 Camaro, aptly named Nemo.
Throughout 2020, Justin had been collecting parts for a build he was planning with another 454SS truck that he had at the time. Parts were rolling in left and right. Complete QA1 OBS front and rear suspension, 20” Weld Racing SR71 wheels (the first set ever in 5×5 bolt pattern), Nitto 555 G2 and 555RII tires, etc, etc. Coincidentally, he had just pulled the LT4/10L90 drivetrain out of his ZL1 to replace it with a bigger, badder, twin turbo/TH400 setup. Can you see where this is going yet?
As things continued to move forward with the parts collecting and truck prep, a new opportunity popped onto the radar screen. Justin spotted a teal ‘93 Silverado for sale and it was fairly local to him. Without wasting any time, he loaded up and headed out to see the truck and it was exactly as promised. 50,000 miles, never driven in the rain, clean as a pin, original owner, original paint. The two exchanged dollars for title and Justin was on his way home with a new-to-him truck painted in his favorite color.
When he got back to the shop, stuff got real. The plans for the 454SS truck were re-directed over to the new teal truck. The decision was made to put the LT4 driveline into the new truck and a new timeline was put into motion. By this time, the Christmas and New Year holidays were quickly approaching. Justin and his tech, Steven Prody made the decision that the truck would be finished in 30 days and they would document it all for their Youtube channel, Stangkilr Productions. Ambitious, but they knew it was possible.
Truckloads of parts were ordered and Steven got to work tearing down the truck. The pristine cab and bed were pulled off the frame and set aside. The old drivetrain was yanked and sold on Facebook Marketplace. The frame was stripped of all of its suspension components and unnecessary brackets and sent off to be blasted and powder coated at Kapowder Coatings in Blue Springs, Missouri. The powder coated frame was returned in just a couple days and the circus of assembly ensued.
The QA1 suspension components were bolted on first to build the basic roller. Tubular control arms and rear multi-link suspension with front and rear coil-over shocks were added along with BellTech 2” drop spindles. The original 8.5” rear axle housing was powder coated and loaded with an Eaton differential, 3.08 gear, and Yukon axles. Gears Unlimited built a one-off aluminum driveshaft with the proper U-joint and flex joints. Massive 16” front and 14” rear brakes with 6-piston Wilwood calipers from Little Shop Manufacturing were next up. If you’ve never seen this kit in person, you are in for a treat. With their CNC-machined aluminum hats and giant drilled and slotted rotors, they work as good as they look. Justin and Steven lucked out when the Weld Racing wheels fit over the brakes with a pinkie space to spare.
Steering duties are handled by a rack and pinion conversion from Elevated Concepts. Their kit provides the steering rack, all of the mounting brackets, tie rods, heavy-duty tie rod sleeves, and everything needed to convert the steering shaft to the new setup. It’s a clean, bolt-on setup that really tightens up the steering feel and offers an option to the sloppy OEM steering box. The guys also installed ECI’s solid LT-swap motor mounts as well as one of their chassis braces with built-in transmission mount to add rigidity to the stock frame. Beefy stuff right there, folks.
The next order of business was sliding the LT4 and 10L90 into the chassis. The combo is physically massive, but fits into the OBS platform like it was designed for it, with ample tunnel and firewall clearance, and hood clearance for days. The Speed Engineering headers fit with minor modifications for clearance around the control arm mounts. A Speartech engine harness was fitted before the cab was lowered back onto the chassis.
Once the cab was bolted in place, the front end of the truck was assembled and the guys got crafty fitting everything in place. A Cordes Performance chiller tank sits on the driver side inner fender along with a Motion Raceworks catch can. The supercharger coolant pump and cooler were strategically placed on the core support. The original coolant overflow tank was cleverly re-purposed as the methanol injection tank. Giant dual cooling fans from LMC Truck were bolted to a 454SS radiator for engine cooling duties. Before the bed was dropped back onto the frame, a new tank and Phantom electric pump setup from Aeromotive was added and plumbed with PTFE AN hoses and fittings.
Once the cab and bed were at home, the details started coming together. A new stock hood replaced the cowl induction hood installed by the original owner and Eddie Motorsport billet hinges were bolted on. A new rear bumper (to replace a dated roll pan), smoothie front bumper, and new grill were painted by Pete Dutzel to match the truck and the crew at KC Detailing proceeded to throw down their paint correction expertise to make the 28-year-old paint sparkle like a teal diamond.
The interior was so minty fresh that all that was required was a quick vacuum and some new car scent spray. The photos in this feature are not retouched or Photoshopped. The interior in this truck looks and smells like a 1993 time capsule. The only additions are the Dakota Digital gauges, a Billet Specialties steering wheel, and the previous owner’s Sony head unit installation. Flip open the glove box lid, and you’ll find the controller for the methanol injection and data port, but they are otherwise well hidden.
As I’m writing this feature, Justin has just returned home from the Lone Star Throwdown where the truck made its public debut at the CK Truck Mag booth. To say people went nuts over this truck is an understatement. The guys at Killer Performance are busy getting the truck ready to go back for more dyno tuning and hope to put down 850+ wheel horsepower. Not bad for a truck built in under 40 days.
Is this the baddest OBS on the planet? We’ll let you be the judge of that, but let’s just say we REALLY like it.