Catalytic converters - The Unofficial BMW M5 Messageboard (m5board.com)

Geach · 31st January 2007, 20:25

Were all e34 M5's built with a cat?

Sebring NL · 31st January 2007, 20:37

Yes, they all have cats. 3.8 uses different ones from 3.6, both monolith type. 3.6 was aimed globally, 3.8 never made it through Californian stds.

IIRC there was some mentioning of Middle East or African cars without a cat, but I think someone concluded there was no such thing. I know that Middle East cars do have a lowered compression, but the cats are there just like ours

davidoli · 31st January 2007, 20:45

I believe that my 3.6 has been decatted.....it sounds soooo sexyyyyy !

Geach · 31st January 2007, 20:53

The reason I ask is that when putting the exhaust back onto my car I decided to use the 'cats' of off the 3.6 I broke a while back due to the heat shielding and general condition being better than mine.They seemed light when bolting them up but I did not take alot of notice.
It was only when I came to fit the o2 sensor that I realised there is no point for it so ended up removing again. My next question then is where did this piece of exhaust come from,if all M5's had cats? Also what happened to the o2 sensor on this car?

farrell · 31st January 2007, 20:56

I think they all had a closed loop catalyst system too.
The 3.6 had ceramic monoliths.
The 3.8 had metal matrix monoliths which allowed for greater flow over the ceramic item for any equal given volume.
The precious metal wash coat could also be more finely & evenly distributed over the metal matrix version due to the more expensive & consistant production methods.

This was still not enough for the 3.8 to meet the evermore stringent emissions laws that had crept up on these cars 3 yrs on from the 3.6

& David, your car has definately not got cats m8

Cheers
Faz

davidoli · 31st January 2007, 22:56

Quote:

Originally Posted by farrell

David, your car has definately not got cats m8 ....and yes , it's the sexiest thing I've heard in an awfully long time FAEPOV !

Cheers
Faz

Cheers Faz.......

BURTON · 1st February 2007, 00:00

I am looking into replacing mine!! G Power..

miles · 1st February 2007, 00:04

Reminds me of the end of production Quality Controll in the Auto industry in the 80`s

On random cars at the end of the production line a cat would be locked in the closed car .

With Mercedes the cat must suffocated after 2 hours.

With BMW the cat died of dehydration.

With Leyland they were happy if the cat was still there when they re-opened the door.

Sorry about the mis-use ,

Miles

Sebring NL · 1st February 2007, 01:02

Miles

Nice to hear from you again!

How's the car and the plane doing?

Hope to see you at the Ring this year

Wout

davidoli · 1st February 2007, 01:04

Apparently he's so keen to have some pax laps this year that he is offering free flights over the ring in exchange.......