My '09 Z06 has only one performance mod done to it, a Maggie TVS2300. Still has the stock exhaust system, stock sparkplugs, everything still stock but the Maggie on top. At only 5 psi boost, it surpasses the output of a stock ZR1. The 427ci LS7 also winds out to 7000 rpm, whereas the LS9/ZR1 only winds out to 6500 rpm. My racing powerband is broader, and when I shift at 7K the rpm drop into the next gear is still above an LS9. You guys should hear what 7K rpm with a 7.0L supercharged engine sounds like, it is dreamy
Here is my dyno graph, comparing the supercharged Z06 vs a stock ZR1. ZR1 at 10 psi boost, Z06 at 5 psi.
And, I think my Z06 looks better than a stock ZR1 too.
I bought the car brand new for $64K. The Maggie kit costs about $7K. For $71K total, you could duplicate the performance of a $110K ZR1. Only thing the ZR1 has on the Z06 is the carbon brakes, but brakes are a simple upgrade too.
Tony