Quad Turbo LS Gets A Workout On The Dyno
The guys from Sloppy Mechanics and Deboss Garage team up to pair a junkyard 5.3 with two twin-stage turbos. Horsepower ensues.
What happens when you have a sloppy diesel mechanic brainstorm with a regular sloppy mechanic? You get the idea to put a two-stage diesel turbo on a junkyard 5.3. And not just one turbo, but two, which essentially turns it into a quad turbo motor. Unlike what you may be thinking, the quad turbo isn’t exactly as it seems. For one, each turbo still takes the exhaust gasses from a log-type manifold, so it’s not like each turbo gets power from just two cylinders. As well, they aren’t in-line, so one smaller turbo is not powering and spooling the larger one. Instead, the way this two stage works is to split the gasses between the two turbos, utilizing the larger and smaller turbines when necessary. It works great on diesel engines, but what about an LS?
Sourcing anything from a scrap yard will yield some issues, and there was no exception here. A few miss-fires were caused by bad plugs, and there were definitely some fuel delivery issues. Once those got straightened out, it was time to tune the motor, but just with the larger turbine making the boost. After the ignition and fuel issues were dialed in, the motor was making over 500 crank horsepower. So, would the activation of the twin-stage turbos blow everything up? Well, actually no. But what they did add was a reported 150 lb/ft of torque at 3000 RPM, right in the meat of the rev-range.
So if someone tells you they want to build a quad turbo LS with diesel turbos, they aren’t as crazy as they sound. Tip of the hat to LS1tech forum moderator denmah, aka Sloppy Mechanics!
