One of the desirable qualities in a track car is the need for the engine to stand up to many hours of abuse. For this, a big, "lazy" engine that is putting out less power than it could is a good thing. A big, naturally aspirated V8 or V10 with relatively low compression, low rpm, and low stress will last longer than a finely tuned tiny engine that relies on high rpm and/or high boost to generate power. How many of the Japanese or German sports cars can spend 40-60 minutes on a track without overheating? (even the so-called "track specific" models?) Viper engines are lazy engines. They were designed that way on purpose. Put a supercharger on them, and you get 800hp. Put twin turbos on them, and you get 1000+ hp. But in stock form, there is a lot of unused potential that translates into track durability. Factory Vipers dominated endurance racing because of their big lazy engines. Having a big, flat torque curve is another benefit of a big lazy engine. So, I guess we have a difference of opinion regarding engine size and track use. I'm definitely a believer that a Viper or a Corvette make great track platforms in no small part because they have bigger engines. The ZR1 is a "straight line beast?" There are only a very few cars that can keep up with a ZR1 on a track. I would not characterize it as a "straight line" car.