Breaking Point

How Much Boost Can a Stock 6l Ls Short-block Take? We Decided to Find Out.

- Richard Holdener

If you are new to the LS scene or haven’t spent much time online, or at events, or near other LS owners, you might have missed the first or second “big bangs.” Originally, the big bang test was designed to find the absolute boost and/or power limit of the factory LS short-block. With drag racers out there laying down some pretty impressive numbers using stock short-blocks, we wanted to find the absolute power limit of the LS platform. Armed with a 4.8L back in 2011 for Hot Rod, we subjected it to some minor top-end mods and a pair of turbos to the tune of over 1,200 hp. We followed that exercise up with the same program on the larger (and more popular) 5.3L for Truckin magazine. The combination of lessons learned and increased displacement allowed us to push the 5.3L over 1,300 hp before things went south. Having run both the 4.8L and 5.3L, this left only the iron 6.0L yet to be tested. Well my friends, that day has come and we finally got the chance to give a Gen III 6.0L LQ4 the old big bang treatment.