I went to the track and trapped 105mph. So I feel the dyno was accurate. I did some digging, found the cam to be in time. Took the exhaust off and found both cats plugged. Bammed them out and went back to the track. Trapped 109mph on a 15 degree warmer day. Not sure if I'll go back to the dyno, but I figure 4mph on a 4200lb vehicle is probably worth quite a few horsepowers. Thanks for the help people.