LS Engines

LS engines are still popular, and for good reason. They are inexpensive to purchase, have a plethora of aftermarket support, and can produce insane power with nothing more than a cam, springs, with an off turbo. It’s a marvel they haven’t taken over the performance world with four-digit power levels so simple to get by! Any LS is fantastic in original trim, but it becomes much better with a few tweaks. All of the tried and proven stuff works, such as heads, cams, and intake manifolds, but boost is what truly makes an LS shine. Applying boosts to an LS is never easier or less expensive, thanks to the wide range of turbos now available for them.

The issue with such widespread availability is that there are nearly too many options. Choosing the proper turbo for your application becomes tough, and once we do, we can’t help but second-guess our decision. What if your preferred turbocharger was either too tiny or too big for your application? To demonstrate how various turbos may alter the power curve of an LS engine, or any engine for that matter, we chose to pit two popular versions against each other in a back-to-back Borg Warner boost battle.

3rd and 4th generation small-block V-8 gasoline engine

Three items were needed to test the turbos: a test motor, a functional turbo arrangement, and (of course) a pair of turbos. We opted to use the Gen 4 Big Bang 6.0L as our test engine. Modifications to the stock low end of the market (SBE) LY6 6.0L included only an increased ring gap after producing 1,543 horsepower at 29.2 psi for Engine Masters TV and Hot Rod. It’s incredible how much power these standard short-blocks can withstand, and the Gen 4 LY6 would still be active and well following over 250 dyno pulls (dozens nearing 1,000hp), including that of the massive power run.

A pair of Carbide insert, Gen X 225 heads from Air Flight Specialisms, a phase turbo cam from Brian Tooley Sports, and (for this test) a Dorman LS6 intake were added to the standard short-block. The Holley Race Sniper that had been utilised on the motor during Big Bang testing was loaned to the Engine Masters folks for additional test on a turbo 5.3L. A factory throttle body, 120-pound Holley pumps, and a Holley HP ECU were also installed on the 6.0L.

After we had taken care of the motor, we needed to provide a boost to it before we could test the turbos. That instead of purchasing a specialized kit, we did what the majority of LS owners do and cobbled one together. We started with original vehicle exhaust manifolds and turned them forward before having JFab construct a 2.5-inch Y pipe. The Y pipe included twin wastegate facilities and ended in a 3.0-inch v-band. Our (made) v-band T4 (or T6) turbocharged barrel adapters were intended to fit the V-band.

Turbo Smart’s Gen V Hyper-Gate45 waste gates were used to fill the twin waste-gate requirements. Spring tensions of 10 psi were used to set up the gates. We also drilled and tapped the Y pipe for a back-pressure sensor in order to collect as much data as possible. The DIY turbo system supplied all of the exhaust energy required by the turbos while leaving plenty of room for cable access. There was also no fear about heating plug wires, which some aftermarket turbo manifolds do not have. The finishing touch was a Procharger aerosol exchanger. We filled the cooler with 90 ° hot water for this test.