i replaced my headers and cat with aftermarket. and i loss torque why would that be?

 

you should go to team-integra.net and search for a very very detailed answer

But for now, think of it as not losing torque, just moving it to a higher location in the RPM band.

Did you dyno this car, do you have the charts to prove you lost torque?

 

Because you probably got a header setup for high end power.