View Full Version : Running With No Converter
fogls
07-05-2014, 11:31 PM
Is anyone here running without a catalytic converter? Aside from the obvious cel and environmental concerns will the Legacy run ok with out it? Some cars are picky about it and others are not. I am going to be redoing the exhaust on my 98 GT Limited and I am looking at all options. Any info is greatly appreciated.
LunchBox04V
07-06-2014, 12:32 AM
I was running a phase 2 2.2 California without a cat for a while in my old wagon. As side from the environmental stuff, you will need a spacer for the second O2 sensor. If the ECU looks as both signals from the number 1 and 2 O2 sensors, and sees no change, it throws a P0420 alarm. (The EJ22 Gen 2 actually had an A/F Ratio as sensor 1, and O2 for sensor 2... Weird California model stuff) Adding a slightly drilled out "spark plug anti-fauler" fixes this because the signals will be different. (All the ECU really cares about)
Aside from that plan on adding a resonator. I initially didn't, and Jesus it was loud even with a large can style muffler. (Only removed the cat). As a whole, I'd suggest against it. I only really did it because thy original cat flang died, and I was not in the mood to spend $500 plus for a new bolt in cat setup. I will say the mpgs increased with the cat removed.
fogls
07-06-2014, 01:02 PM
If I decide to go that route I will definitely be running a resonator. Thanks for the info.
Wiscon_Mark
07-10-2014, 12:39 PM
I would go with a hi-flow cat instead - it's going to be loud, boomy, and raspy, even with a resonator with no cat in there, and it's a terrible for the environment.
r3v_v3ng3
07-13-2014, 04:16 AM
+1 on the high flow cat. You guys are lucky you can get them off the net, its a no no in CA
Huffer
07-14-2014, 12:20 PM
I always run without cats. Too much weight, especially with my Asics trainers.
Plus they're always hissing and start biting a bit if you squeeze them too hard.
Oh WAIT. You mean a catalytic converter for a car!
The ECU will trip an error unless you cap the sensors away from the exhaust flow you could install a resonator in place of the cat, but you will still need to consider that your car will trip an error at some point. Plus, if you have EPA inspections they could fail you just on visual inspection alone.
fogls
07-27-2014, 06:14 PM
I live in Michigan. No inspections here.
lancerswimmer89
12-12-2014, 04:08 PM
I too am from Michigan, and have no cat, just a resonator
WRXish
04-03-2016, 04:59 PM
I live in a part of VA that they look to see if the cat is there during the annual inspection, but thankfully here there is no tailpipe sniffing going on. The folks in NOVA unfortunately have to suffer through the emissions test. For me, thats reason enough not to live there. :) Giving serious consideration on my old 91 wagon gutting the cat and leaving the shell on it...it will pass the visual inspection that way and no doubt run better. It may be more trouble than it is worth to do that...
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