As Dave has already mentioned above , the first thing I would do is install a fuel pressure gauge where it can be viewed while going down the track. According to the Wallace calculator linked to above , your incrementals all seem to fall pretty much in line. It may be that your power level is just a little lower than you had hoped. If the engine is essentially a 440 magnum with headers , it may not be too far off the mark. Are you running a full exhaust system ? I had a low comp 440 in a 71 RR back in the 80s . 2 inch exhaust with glasspacks: 93 mph. uncorked : 102 mph. Couldn't believe it.