I have slp 1 3/4 headers, flowmaster catback, and a airfoil. What should i do to my car now ??

 

Start scanning ALDL data (see the DIY_PROM forum under Craig Moates software) and see where the current software is out of tune. With your Speed Density setup, the headers most likely altered the engine's volumetric efficiency and the software won't accomodate it very effectively without tuning.

If you see deficiencies in the ALDL data you capture...spots in the part-throttle RPM range where BLMs are out of the 128 +/- 4 range, a lot of knock retard or incrementing knock counts, or at WOT the O2 sensor very far off 920mV, you are missing out on engine efficiency. $200 worth of tuning software and PROM burner gets you set up to adjust things to match your engine setup.

 

while i didn't understand that.......

it sounds good.

next i would do a good custom intake. a full exhaust system and a good intake to free up the breathing of my L98 brought me into the 13's.