Sleeper Silverado Build Hides A 1,500 Horsepower Twin-Turbo LS

Tolman Performance is closing in on a sleeper Silverado build. The truck looks like a mismatched shop rig, but it hides a twin-turbocharged 6.2-liter LS. Two GTX3582 turbochargers power the combination, and the truck should make 1,500 horsepower once it’s finished. Tolman expects mid-to-low nine-second quarter-mile passes once the truck hits the track. Reaching that point has taken weeks of fabrication work, and most of that work centers on the charge piping and the wiring it displaced.

What Powers The Sleeper Silverado Build

Twin GTX3582 turbochargers sit at the heart of the combination. Custom intercooler tubing routes boost to the engine, and dual O-ring couplers seal each connection. Tolman sourced the wastegates and blow-off valves that control boost pressure through Summit Racing. Most of that hardware is already fabricated and mounted. The wastegate dump tubes still need to be built, and the whole system still needs final plumbing.

Charge Pipes And PCM Relocation

Tolman built the 3-inch charge pipes to clear an upper AC hard line on each side of the engine bay. He bent the driver’s side tube around the line first, then shaped the passenger side to match it as closely as possible. The new piping ran straight through the factory location for the powertrain control module, so the PCM had to move. It now mounts on the truck’s original battery tray, using a bracket from Off-Road Anonymous. Tolman welded bolts to the tray so the bracket sits level and won’t twist when it’s torqued down. Then the battery was moved to make room for it.

Rerouting The Engine Harness

The stock engine harness normally runs directly over the turbo location. Instead of stretching it out of the way, Tolman rerouted the entire harness underneath the brake booster. That meant lengthening every wire in the harness, not just the ones in the way. The list includes all eight injectors, all eight coils, the coolant temperature sensor, the MAP sensor, the cam sensor, and the crank sensor.

With the charge pipes and PCM relocation done, Tolman still needs to build the wastegate dump tubes, wrap the harness, and finish the battery cables. Once that’s finished, he plans to start the engine and check the cooling system for leaks before wrapping up the rest of the fabrication work.

It’s easy to dismiss this Silverado as another rough-looking shop truck, but that’s exactly what makes the build so appealing. Beneath the weathered exterior is a carefully engineered twin-turbo LS combination with the potential to produce 1,500 horsepower and run deep into the nine-second zone. More importantly, Tolman’s project is a reminder that big horsepower isn’t just about bolting on a pair of turbochargers. The fabrication, wiring, and countless small details are what separate a running project from a reliable, race-ready machine. Once the final plumbing and electrical work are complete, this unsuspecting Silverado looks poised to become one seriously quick sleeper.