mattofiesh

What’s up guys, I recently had a 4v head swap done to my 98 gt. The car is different at a high rpm but almost seams sluggish for the first few thousand rpm’s. I have a auto trans with a shift kit and 3.73 gears, short tube headers with high flow cats 2 ½” exhaust and other stuff. The shop said im putting 264 hp on the ground but doesn’t feel much quicker then before. I don’t have pre swap #’s but my best old 2v npi ¼ mile time was 14.2 and haven’t made it to the track yet. I am looking for suggestions to get this thing jumping up to speed quicker. Thanks for any help