$2000 for 5 rwhp

[97whitecobra]

I have a 97 cobra with the usual bolt ons. Recently added fully ported stock intakes and the imrc deletes. This was supposed to get me about 30 to 40 horse gains after 4500 rpms and 20hp at the peak. I lost low end torque and 5 to 10 low end horses. Only gain was from 6200 rpms to 7200 where i gain from 4 to 20hp. Car went 2 tenths slower. It was a hotter day by 20 degrees, but still. what mods does it take naturally aspirated to get 305 hp at the rear wheels? and what about shortys? Thanks.