i do not think you ran a 280 roller cam in a small block ?? on the street?? i am talking at 0.50 dura not adv dura .this is one big cam you can run somthing this big in a big block but you shure in the hell know it in there 280 at 0.50 and the lobe sep do not help that much when the cam is that big i know i had them at 112 110 108 and they all were choppy