I am considering installing a Cold Air Induction System on my ZR2 with the GM's OEM part 8453531. In calling two local dealerships about purchasing the part, naturally they provided two different prices, I was implicitly told by both service departments that if the cold air induction system is not installed by the dealership, this particular item would void the factory warranty. When I questioned as to why, the service department representative, told me, items such as tires, shock, visors, and exterior add-ons and etc won't impact the warranty . But, this particular product because it involves electrical system and particularly the emissions system that it has to be installed by the dealer, otherwise it would void the warranty if the truck experiences engine, electrical or problems involving the emissions systems. Does anyone know specifically if these statements are true? I am actually surprised that if they aren't, that GM doesn't specifically conduct quality control and conduct random checks of the dealers for honesty. The two dealers in addition to cost of the cold air induction, more than $500, the installation charge exceeds $250 not including tax. Although one of the service techs bragged about claims of noticeable improvements in HP, Gas mileage and torque, he couldn't provide specific numbers with the exception of gas mileage which I can expect between 1-3 mpg improvements. I'm curious if he is simply attempting to sell a product which if I do purchase, I will be greatly disappointed if I don't get the improvement in HP, torque and mpg. Anyone have any facts that help me make the best decision?