Im still not sure if I should put a new cat on after i fix my plenum, i have the po420 codes and came to the conclusion with help from here that the cats probably bad. Anyway i dont have to smog so should i even bother putting this magnaflow cat on, heard you get better power without a cat, what about gas? what are ups and downs to cats? again i dont have to smog so thats not an issue. Also if i dont put a cat on and i use a y and a pipe instead would this be better? thanks everyone

 

A Y with no cat is gonna be your best bet. Just sell the magnaflow and put that money towards the exhaust. I paid 65 to have mine cut out.

 

so i would just weld the y on, and add a straight piece of pipe and do the spark plug foul trick for the o2's and call it good. So this would be better flow altogether right? my cat now acts as a y so i would have to cut the pipes where they go into the cat and add the y. Also should i try to get some stainless pipe that run down from the headers or just use the stock ones?thanks

 

You can get a 'replacement' y-pipe (supposedly for off road use only....) that is a direct bolt on replacement for the current Y-pipe, and cat...... even has the bungs for both O2 sensors, just use non-foulers on the rear O2, to fool the PCM into thinking the cat is still there. You will like it.

 

i only have two o2s so would i still use the non foulers? have a link to this offroad y? I have a 97 1500 4x4 5.9 thanks

 

check out jegs.com

 

looks like that offroad pipe isnt stainless steel like the magnaflows, how do you think itll hold up? dont want it rustin itself away

 

You'd use the non fouler on the 2nd O2 sensor, the one that went behind the cat. The first one, before the cat, you don't want to use a non fouler on, as that helps the PCM determine the A/F ratio and doesn't have anything to do with the cat.

 

You're stock exhaust isn't stainless either. It'll last for a long time.

 

so does this have the flanges to connect to the headers? also this is offroad only so if i get pulled over might get a ticket if they see it right? what about a magnaflow y is that illegal also if i have no cat on?

http://www.jegs.com/i/JEGS-Performan...33#moreDetails