Roughly a year ago, we were going gaga over German-based Geigercars Corvette Z06 Black Edition which upped the horsepower of the already potent LS7's stock 505 horsepower to 592. It seems lately that tuners can't get enough horsepower or so Geiger installed a couple of turbos on the now venerable Z06 and painted it neon green to make sure people see it coming. The result? Geigercar's 890 horsepower biTURBO Corvette Z06.