Purple Cam Design Question

The Mopar Purple cams were all redesigned in the mid 1980s to take advantage of the .904 lifter diameter. This is actually in print in the latest edition of the MP engine book. While it's true they are an old design, they still work well. There are simply some instances (more often than not on the street) where you just don't need lightning fast rates of lift. In fact, it can be really bad on the valvetrain in some cases.