Joe Jill has been running Superior Automotive (and its forbear, Speedwin Automotive) for the better part of 40 years. Through it all, he’s seen ’em come and seen ’em go. From the 426 Hemi to the 396 Rat, to the Boss 429 to the AMC 390, Jill’s been on the ground floor when it comes to developing the latest Detroit powerhouses. Even with such righteous previous encounters, Jill admits few engines have impressed him for sheer potential as much as the Gen III Chevy LS1 small-block. He says it’s the first engine to be designed from the ground up with zero compromises, a true tour de force for the emerging art of Computer Aided Design.
But when Joe says, “The factory really did a great job with this one,” that’s another way of saying, “But watch out after we get done with it.” In true form, Joe has polished this gem to even greater brilliance by the simple addition of a package consisting of a hotter SLP cam kit, a high-flow LS6 intake manifold, and some very basic yet highly effective head porting and cleanup work. The end result on the test ’98 Corvette—which already had headers, a performance computer, and an upgraded throttle body—is a jump from 316.2 hp and 324.4 lb-ft to 375.7 hp and 362.5 lb-ft at the rear wheels on Superior’s Dynojet chassis dyno. That’s an easy 400 hp at the flywheel and nearly a full second at the dragstrip. Watch and see how it’s done.
