While that is true, the OP is talking about a H/C LS1, not a cam-only LS1. Sometimes that doesn't mean much (like in my car's case), but sometimes it's more than enough to make it a good race for a cammed Z06. There are many many H/C/I LS1 Fbodies making high 400s to the wheels, which is plenty to hang with or sometimes beat a cammed C5 Z06.
His setup is a cammed ZO6 motor....he has the LS6 heads....and I assume an intake(could be wrong, but why do 2 without the 3rd?)
I may be off the reservation here, but isn't the difference in the LS1 and LS6 h/c/i?