That said he really butchered the fenders and quarters... for some reason?
Yeah, that doesn't make any sense. I would bet money it would have been faster with tiny 225/45R15 BFG Rivals on it on stock 15X7's that with those Camaro wheels and adapters.
The only thing I can think of it still has the soft V6 springs and his wheel adapters spaced the wheels out too far and the tires rubbed the body.