What year Corvette do you have? The 2002's are 50 state legal so the emissions are the same for everyone. Previously, in 2000, you got a pair of extra cats. I believe in 2001 everyone got the extra "pup" cats. If the material in those "pup" cats were to somehow fall out, you'd see a slight performance increase...IMHO
Bob
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2000 Mil Yellow Coupe (sold),
2002 Mil Yellow ZO6 build week 8/20
Trackside delivery Justin Bell School 9/12