The dimensions on these cams are like a lot of older grinds - long duration with less lift than more modern cams. So ideally you're going to need a decent amount of static compression to make them work well but they seem to do OK even at low compression ratios also. We ran the 284 cam in a 9:1 440 with 906 heads at 3300# in a '68 Dart. Best time ever was 11.33 which we thought was OK. When we wanted to swap cams Dwayne Porter was nice enough to spend some time with me. He explained that they have a broad power curve and actually make pretty decent race cams. I remember him telling me also that they will RPM better than most modern "fast ramp" type cams making them a decent choice even now.