Reg. Duty 390 Rear (Includes 850.00 Core)  E-mail this product to a friend

ratio differential. C5's equipped with 2.73's will get up to a full second improvement in 1.4 mile E.T.'s, while 3.42 equipped cars will get up to 4 tenths of a second improvement. There are two

options available for the output shaft; for six-speed cars with engine horsepower in excess of

450 we suggest the severe duty version, automatic equipped cars, unless running nitrous, superchargers or drag slicks, will be properly equipped with the standard duty version.

Reprogramming of your speedometer will be required and we suggest the Hypertech Power Programmer (it's easy to do).