The spring steel roller lifter retainer is also known as a spider. It's the tip-off that the Ford roller lifter configuration will be used. The other alternative is lifters that come in pairs already joined together with a tie bar. They don't require a spider for lifter orientation in the bore. The camshaft is a Comp Cams roller grind that Smeding has specially made. It features 0.565 lift on the intake and 0.574 on the exhaust, measured at the valve. The duration at 0.050 lift is 232 degrees for the intake and 240 degrees on the exhaust. The lobe separation is 112 degrees. Although this might be considered a big cam on a 302 or 351, the 427 ci of displacement in our engine will absorb that much capacity with ease. The result will be an engine with instantaneous throttle response anywhere in the rpm band.