just got true duals tossed on my 94 z today... stock manifold... no longtube headers or anthing... just true duals done at a local shop... 481.50 out the door. sounds amazing... cant tell a hp gain... but i agree with the above that it willl come with installation of good headers.
$Glen$

 

hahaha back from the dead...... if anyone reads this forget what i said a year ago about the backpressure i was way wrong.