With the upcoming release of the Corvette ZR1 I am caused to reflect upon the previous generation, and how in fact the LS9-motivated hunk of carbon fiber measures up to its C4 predecessor. I think it goes without saying that the new 638hp, supercharged ZR1 is nothing short of primal in its capabilities. The chassis undeniably benefitted the most modern technology with the addition of safety equipment, lightweight materials, harmonics dampening, fit and finish, style, suspension design, weight distribution, etc. However, I keep wondering how the LS9 compares to the LT5. In a results driven society, the obvious answer is that even the 405hp version of the LT5 was a slug compared to the highly efficient 6.2L Gen IV. But, in the realm of engineering the LT5 is seemingly a much more sophisticated piece that relies entirely on natural aspiration. From its Nikasil coated cylinders, which is known to be far superior to cast iron cylinder liners in terms of heat conductivity as well as friction and wear, to its dual overhead cam and 32-valve head design, the LT5 would be considered cutting edge even today. Despite having 26 more cubic inches and the use of modern technology, an LS3 makes only 25 more horsepower than a later version LT5. So it stands to reason that with a supercharger an LT5 would most likely be on par with the LS9...not bad for early 90s technology.
But for those of you who read Editor Rick Jensen's article in the April '08 issue, you know the LS9 isn't simply an LS1 or even an LS3 with a supercharger strapped to it. From the forged rotating assembly with piston oil squirters to the stiffened block, 9-bolt flywheel, sophisticated fuel and E67 computer–GM went to great lengths to make sure the LS9 would hold up through extreme durability testing. In fact, inside sources say the LS9 is one of the most durable Gen IV motors tested to date, despite also being the most powerful. That being said, the LS9 may not have came from a clean sheet of paper like the LT5, but it certainly didn't recycle one part at the cost of performance or reliability. In the end, despite my love of automotive history, one of the most beautiful sounding American V8s ever made, and the innovative thinking that went into the original ZR1, I'd have to give the advantage to the new-comer. Long live the LS motor!