They are poo poo dog cams. Unless you have a3k stall, 3.91's 10:1 (or better) good exhaust (headers)RPM intake (or like), good carb they are dog cams. They don't pull until 3k or better, make no power down low. If you have all the above they will work pretty good however they are not a good street cam. They have terible idle quality and pull zero vacuum.