Nothing special under the hood. The only mod here was a K&N filter Russ had recently added. Keep in mind that buying a car with modifications is both good and bad. On the good side, you end up paying pennies on the dollar for those mods. Just make sure they were installed correctly so you won't get screwed when you go to smog or register the car. Mods can also be a tip that the Camaro has been run hard. If you see that the car has, or had, nitrous solenoids, are you really going to believe the seller when he tells you he never got around to filling the bottle?