3.6 vs 3.8 exhaust - The Unofficial BMW M5 Messageboard (m5board.com)

Mmm-Five · 4th July 2007, 16:46

Anyone have any pictures to show the difference between a 3.6 and a 3.8 exhaust. I know BMW list different part numbers for them, but just where are they different - i.e. are the back boxes the same?

On another point, what is the concensus on the best (quality) replacement system as it looks like I can't get my original one down from Scotland until September at the earliest and don't know if stainless flexi-pipes from the cat replacement pipes to the back box are legal.

farrell · 4th July 2007, 16:50

The same system from tailpipes back apart from flanges to mount to catalyst back flange.
Cats are different between 3.6 & 3.8 as previously detailed.

Cheers
Farrell

IvanDias · 4th July 2007, 16:53

I was under the impression that the exhaust was the same except for the coating on the catalytic converters. The 3.8 had a different cat which worked better at higher temperatures.

(One was metallic, one was ceramic but I don't recall shich way round it was)

I thought that the units were fully interchangeable from the headers (manifold) back going from 3.8 donor to 3.6 recipient.

Ho hum, can always edit this later if I'm spectacularly wrong!! lol

Regards

Ivan

IvanDias · 4th July 2007, 16:54

Nice, I type and Farrell beats me to the punch!

At least I was not horribly out!

Regards

Ivan

farrell · 4th July 2007, 16:56

M8.
You are never far off the mark

Faz

Mmm-Five · 4th July 2007, 16:59

Thanks guys, it looks like I can buy one of the ebay ones then and get my 'Q' car noise level back.

I suppose I can chose whether to use the cats or not, but I'm not sure what's been done with the O2 sensor as the original cats are not there.

PS. what's involved in fitting these - as so far I've only been replacing 2-3 foot sections whilst the car's be on a ramp!

Sebring NL · 5th July 2007, 03:01

IF you don't have a transmission jack stand thing, don't get started. Exhaust is heavy, my mechanic and I spent some time getting it right on RacerZ's Touring last week

BURTON · 5th July 2007, 10:00

Heavy is a understatment. Its like lifting a 32" Widescreen TV (CRT). Amazing that they are so heavy. but have been done for a reason.

Jahangeer · 5th July 2007, 10:43

Quote:

Originally Posted by BURTON

Heavy is a understatment. Its like lifting a 32" Widescreen TV (CRT). Amazing that they are so heavy. but have been done for a reason.

I think I read they have two layers of steel, and yes they are very heavy, I could just about carry my whole system, the SS was a one hand job

I have also heard from Karl, that the skin can sometime disintegrate and the exhaust note gets louder???

farrell · 5th July 2007, 10:45

The exhausts on E34 M5 from manifolds to tail pipes are a quality engineered part.

You can weld them & patch them...they still come back for more.
If only everything else in life was so reliable & performed as well.

Faz