M42club.com - Home of the BMW E30/E36 318i/iS

DISCUSSION => Engine + Driveline => Topic started by: rufiox426 on September 22, 2008, 03:09:32 AM

Title: Catalytic Converter ?
Post by: rufiox426 on September 22, 2008, 03:09:32 AM
so i need a new catalytic converter, i was planning on getting this one

http://store.summitracing.com/partdetail.asp?autofilter=1&part=MPE%2D94004CA&N=700+115&autoview=sku

or this one

http://store.summitracing.com/partdetail.asp?autofilter=1&part=MPE%2D94005CA&N=700+115&autoview=sku

anyways which one would be a better fit for my 1992 318ic?

i've read that stock piping is 2.25 in. but when i look around on partsamerica.com its suggesting that i choose the first converter (first link) which is 2 in.

also, if i bring it to a muffler shop, since the catalytic converter is a straight design, mine is a little slanted like this / right before the exhaust manifold, do you think they would charge to bend or extend the pipe? also what it the average cost to install a catalytic converter? in CA?

thanks in advance.
Title: Catalytic Converter ?
Post by: rufiox426 on September 23, 2008, 12:32:06 PM
bumpity bump bump
Title: Catalytic Converter ?
Post by: Jimmy Lewis on September 23, 2008, 01:24:27 PM
What makes you think you have a bad cat?
Title: Catalytic Converter ?
Post by: rufiox426 on September 23, 2008, 11:36:37 PM
doesnt pass smog high Nox
Title: Catalytic Converter ?
Post by: rufiox426 on September 25, 2008, 03:27:25 AM
nox is above 2000
Title: Catalytic Converter ?
Post by: romkasponka on September 25, 2008, 04:06:06 AM
Quote from: rufiox426;57274
doesnt pass smog high Nox


You should make engine diagnostics...
Title: Catalytic Converter ?
Post by: rufiox426 on September 30, 2008, 11:04:05 PM
how so?
Title: Catalytic Converter ?
Post by: Cobra Jet on October 01, 2008, 09:39:21 AM
how old is your O2 sensor?

what gas (octane) are you using?

when was the last time your oil was changed?

when was the last time the car had a complete tune-up?

when you went to inspection, was the car operating at normal temps, or was it "cold"?


High NOX can be caused by any of the above, not just a "bad" catalytic converter.  I would check the simple things before dropping $$$ on a catalytic converter and the install (labor, etc).
Title: Catalytic Converter ?
Post by: rufiox426 on October 01, 2008, 12:20:18 PM
o2 sensor about 2 months old

91 octane

oil was changed 2 weeks ago --- royal purple 5w30

i dunno what a complete tune up is but...hmmm

new k&N air filter, oil filter, spark plugs, new vacuum hoses, intake manifold cleaned out, fuel injectors cleaned, and soon ill have new tranny and diff fluid.

i drove the car around for 30 minutes before i went to get it smogged


i did all that. the last time i tried to get it smogged was 6/23/08.

i just want to make sure it passes smog, but i didn't mind dropping money for those parts, i wanted to replace them anyways. i plan on replacing everything. :rolleyes:
Title: Catalytic Converter ?
Post by: ponchiz318 on October 03, 2008, 02:56:33 PM
hmm, I didn't pass emissions here in Texas either. My Nox was also above 2000. I did a carbon clean out and it dropped it to 1400. Still not legal, but did a big difference. Try that. But then again, my car needs a tune up now.
Title: Catalytic Converter ?
Post by: deltaneo1 on October 14, 2008, 11:54:08 AM
if you want free flowing but the look of a cat get a long screwdriver and hammer and pound out the honey combs inside it... depends on state and the place you take it to for inspections... some states just look to see if it has one some to a exhaust test....
but thats what i did to 1996 GST eclipse.. and passed every time...lol suckers
Title: Catalytic Converter ?
Post by: ak96ss on October 14, 2008, 01:31:30 PM
Quote from: deltaneo1;58502
if you want free flowing but the look of a cat get a long screwdriver and hammer and pound out the honey combs inside it... depends on state and the place you take it to for inspections... some states just look to see if it has one some to a exhaust test....
but thats what i did to 1996 GST eclipse.. and passed every time...lol suckers


Doesn't help much on the tailpipe or dyno test, though.
Title: Catalytic Converter ?
Post by: deltaneo1 on October 15, 2008, 10:19:02 AM
Quote from: ak96ss;58510
Doesn't help much on the tailpipe or dyno test, though.


Really ?? I would think it would help out a little... It worked well on my eclipse but that was a turbo. i did 3 inch down pipe and 3 inch exshust all the way back with a flowmaster. I sounded really cool and really deep it was like a corvette like sound. And it seams that everyone has there own idea on if turbos need back pressure or not ... I went with that the turbo dosn't but im sure there are people that would say they do and say they dont but besides that. It was a really easy job to do... I took the CAT out and pounded out the guts and then welded it back in... It would be even easier if the CAT ( like on some cars) bolts on with clamps...
Title: Catalytic Converter ?
Post by: Jak318 on October 15, 2008, 01:04:45 PM
Quote from: deltaneo1;58502
if you want free flowing but the look of a cat get a long screwdriver and hammer and pound out the honey combs inside it... depends on state and the place you take it to for inspections... some states just look to see if it has one some to a exhaust test....
but thats what i did to 1996 GST eclipse.. and passed every time...lol suckers


That same honeycomb from the OEM cat that you trashed is worth almost $200 at a scrapyard now...

Point being if you are going to do that make sure you take your OEM cat to the scrap yard and you should get enough money to buy your new aftermarket one and have it installed.
Title: Catalytic Converter ?
Post by: Jtuner on October 16, 2008, 04:23:56 PM
Just a tidbit, and I don't know if this will help or hinder your situtation BUT,, NOX is created by a lean fuel condition.. more air, less fuel = more NOx,,, thus the problem with the Fuel Stratified Injection (FSI) in america,, stratified uses a very small spray of gas at the last second before combustion, thus creating a large amount of NOx.. extra cats take care of this in germany, but americans don't pay for anything extra, so we settle for Fuel Straight Injection instead :P
Does this help you in your situation, I dunno, but that's the theory behind NOx anyways lol