I hate to say that Intense N/A cam may be part of your problem if I had known you were going to do a top swap I would have steered you away,I just looked at the mods on the test ZZP M-90 dyno Regal and they got 253whp and 300 wtq this is on a 150k engine with only u-bend and resonator delete and a open cone,the good knews you can drop pulley sizes to a 3.4 fairly safely with your mods and a custom tune from a knowlegable tuner should help.Chico.