Steppin' up to some real power, this aggressive cam is intended for custom built engines 402ci and larger with at least 11.0 to 1 compression ratio and 225cc heads.  This cam with its 231/237 duration, has a really choppy idle and the .592"/.599" lift requires pistons with larger valve reliefs and our 6.vps515 valve springs.  This is an awesome cam for a track day car that is still streetable.  Not suited for smaller displacement engines if intended for the street.  Hardened pushrods required.