Have been considering the stainless si/so systems from Borla, Corsa, and Banks. They have hugh pipes ( 3 and 3.5 inches ), will this reduction in back pressure hurt performance at low (normal driving) rpm. They all advertise hp and torque gains at high rpm. What effect will these systems have on low rpm torque, will they have the fuel efficiency at normal rpm ranges (1500-2500). Does the 304T stainless mufflers really late a lifetime?

 

some good reading...

 

This is a good article that anyone considering an exhaust performance upgrade should read. I requested some dyno data from Banks to make a comparison.