S2 Pro series cams are no joke. As mentioned above they are not a drop in and go cam if you are using a high compression piston. If your motor is spec'd and permit the use of these cams I highly recommend them. High compression and these cams go hand in hand, but be ready to buy a new motor if specs are not just right. Make sure you are using supporting valve train also. I am using the Pro1's and love the results.