IDK if this cam is available in three bolt but if it were me I'd opt for a more modern cam. I'm not saying its the wrong cam or that it would not work well. What I am saying is from what I read about it its a replica of a cam that was designed decades ago
It is not a replica, Comps replica cams are called Factory Muscle. the 21-305-4 is their Magnum Muscle, "a step up from the original 383-440 magnum cam". call comp cuz I think for a few dollars more they will make it a 3 bolt
