I built a 454 to put in my c10 and it is not pumping. I know the pump is working because i pumped it by hand to make sure it worked. It seems that the fuel pump pushrod is not pushing out far enough to work the pump and it was a new rod. I used one off of another 454 but i had the same problem. I would like to know if maybe that there could be a problem with the cam (i installed an comp extreme energy cam) if anyone has any suggestions i would love to hear them.