12 Besides the fact that most Street Stock classes won't allow a hydraulic roller cam anyway, the stock unit (top) only has a duration (at 0.050 lobe lift) of 208 for the intake and 221 for the exhaust. The Comp Cams solid flat tappet cam meanwhile specs out with 240 and 246 degrees of duration at 0.050 and is much more aggressive getting there. There is also another unique feature of this cam we are excited to try out. Notice how the lobes near the cam's journals beefed up with extra material. Comp now offers these special cores that are designed to significantly stiffen up the camshaft. By reducing cam flex it should help reduce the chances of wiping a lobe on these super agressive flat tappet designs as well as help control the valve opening and closing events more precisely for additional power.