the zo6 has rear brake vents and has a more aggressive stance like the zr1 the zr1 has a supercharged 6.2 that puts out 638hp and the zo6 has a 7.0 that puts out 505hp and the base has a 6.2 that puts out 430hp and there is a grand sport witch is more like a zo6 handling wise but has the base 6.2 and it has the rear brake vents