The Corvette ZR1 never needed more horsepower. That didn’t stop John Hennessey from adding 100 horsepower power to the ZR1. Although the ZR1 was powerful enough the extra 100 horsepower has some dramatic effects.
The Hennessey HPE850 Package for the ZR1 includes some serious upgrades to extra this extra power. A Smaller lower pulley, Long Tube Headers, and a better induction system. The resulting performance is 0-60 in 2.6 Seconds and a quarter mile run of 10.3 @ 136 mph.
The increase in performance is no joke. A Stock ZR1 can only sprint form 0-60 in 3.0 seconds. The best part is these are very simple modifications that you could do at home. Besides the custom ECU tuning, you could take your ZR1 at home throw on a smaller pulley, install a new exhaust, and then upload an ECU flash.