I've hit a 15.3 with my crx dx with the cat, stock piping and magnaflow, now I have no cat, 2.25 piping, glasspack, and dynomax performance muffler, so basically my exhaust is straight through, and I went from 15.3 to 15.6, and my trap speed went from 90-91, to 88-89, im really kinda pissed that i got slower from doin full exhaust. Is back pressure needed for my dx motor? ive ran open header a long time ago and it didnt seem to make any difference, if anything it was slower. Im considering now to have the cat welded back in.... any experience is appreciated, and if any guys from H-T were at atco tonite, i was the red 88 crx.

 

You could have had a bad night maybe; any number of variables could have changed, but loosely I would base the change on Torque numbers dropping.

 

bump

 

If I were to get a Hi-Flo Cat, would this be enough to provide back pressure, or should I just weld in my stock cat? It seems like my car performs better with the cat than without.