Anyone tried using a magnaflow universal catalytic converter on the e34? I'm gonna get my exhaust system checked to see if my cat is clogged. A few months ago (before the headgasket and head change) i was burning coolant (White smoke) and ive heard that this could gum up the converter and cause excess backpressure. I'm suspecting this because under hard throttle the exhaust gets a funny smell, and because the throttle response is more sluggish than normal, even after i replaced the air filter. anywho, any recommendations on a new cat? Is the magnaflow cat a good idea?

if your bent set on buying a new cat, try drilling a few holes in the cat first to see if your throttle comes back. I did that once on an old chryslter mini-van, and i got 50k more miles out of it...well my dad did, anyways, it freed up the throttle.

If your cat was clogged, you wouldn't be able to drive the car. If there were anything "gummed up" and the cat had any flow, the heat would have long since burned it off. An easy way to tell if the cat is working fine is to check the temp going into and out of the cat.

http://www.aa1car.com/library/converter.htm

straight pipes!

Is the magnaflow cat a good idea?


+1 i'd like to know this. I'm thinking about putting on magnaflow cats when I put my headers on and selling the stock cats for scrap metal

magnaflow cats are great. I had 2 on my 540i before I sold it. Not a problem with them at all. To check if your cat are OK.. Just use something and knock on it. If you hear rattling sound then it need replacement. If it is solid then it is still good. You dont really gum up or melt a Converter unless you are running turbo at high boost and run it extremely rich.

http://memimage.cardomain.net/member_images/6/web/2358000-2358999/2358062_27_full.jpg

I installed 4 magnaflow cats on my ML55

Sounds good. and you didn't have any problems passing CA smog with the magnaflow cats?

Ive had a magnaflow cat on my car for about 3 weeks now. The only regret I have was getting rid of the resonators. It made it raspy as hell at certain RPM depending on throttle position. It sounds great at WOT though. So to take care of the raspyness I have a Borla muffler on the way :) . Ill post a sound clip whenever its all said and done.

I'm on the same boat with the cats on my 97 540i I was thinking about going with the magnaflow until a bmw shop told me that if I didn't replace them with the original cats the oxygen sensors would't work correctly and it throw on the CEL. I'm still debating.

I'm on the same boat with the cats on my 97 540i I was thinking about going with the magnaflow until a bmw shop told me that if I didn't replace them with the original cats the oxygen sensors would't work correctly and it throw on the CEL. I'm still debating.

:lol

Cats are after the o2 sensor...

I installed Magnaflows last year on mine, and the car didn't pass smog this year. I am waiting on my D.E.C. Converters from BavAuto as you read this. First thing I noticed about the Magnaflows was that they were about 1/2 the size of the stock cats (about 1/3 of the price as well...).

I installed Magnaflows last year on mine, and the car didn't pass smog this year. I am waiting on my D.E.C. Converters from BavAuto as you read this. First thing I noticed about the Magnaflows was that they were about 1/2 the size of the stock cats (about 1/3 of the price as well...).


ooo... that's the part that scares me. I'm worried if use magnaflows i won't be able to pass CA smog

ooo... that's the part that scares me. I'm worried if use magnaflows i won't be able to pass CA smog

Truth be told - go for the good ones. You can't lose. And I'm in Georgia - a lot easier to pass here than it is out there.

ooo... that's the part that scares me. I'm worried if use magnaflows i won't be able to pass CA smog

Eric,

Talk to Emmanuel... He'll know what to do.

FYI, I had him install Magnaflow cats on my 4runner when it didn't pass smog. After switching, I passed fine (twice)

Eric,

Talk to Emmanuel... He'll know what to do.

FYI, I had him install Magnaflow cats on my 4runner when it didn't pass smog. After switching, I passed fine (twice)

That sounds like a good idea. I'm gonna have him install my headers and was thinking about putting on magnaflow cats at the same time. and then selling the stock ones for scrap