OK. I'm sure I'm not the only one out there who'd like to know, Who has ever run 1/4 mi. comparing OEM cat back exhaust on 3rd gen/TPI/TBI/4BBL,vs hi-po cat back system, flowmaster/dyno-max ultra-flow/SPL/Borka?etc. Cast iron or headers on BOTH tests, not just headers on aftermarket cat-back. I'm curious at a fair-even comparison, just wondering what all the aftermarket cat-backs are really worth in the 1/4 mile, and on the street too for that matter. Lets hear your times.

 

My 91 Z28 L98 ran consistent 14.1x's with the factory exhaust and 87K miles. all I can tell you my car was louder after i put the flowmaster muffler on.

 

As I recall, Chevy High Performance found that they gained 2/10 second on their 87 Camaro by changing the cat-back alone.