Back in January we got a preview of Hennessey Performance Engineering's upgrade to Chevrolet's Corvette ZR1. HPE's Z700 Corvette ZR1 includes an extensive list of bolt-on parts combined with a custom tune to boost the standard 638 horsepower ZR1 to 705. And to prove this car is a contender, Hennessey is planning to run the Nurburgring later this year.