Difference between 'i' and 'ix' catalytic converter section + headers

[eugeman]

I just bought a automatic 325ix and it is missing the entire exhaust from the exhaust manifolds back.

I know the rear muffler section is the same as any other 325i, but my understanding is the cat section is different.
Can anyone tell me what the differences are? I know it's a long shot but pics would be a huge plus!

Even aftermarket replacements cost an arm and a leg & trying to find a good one used seems to be impossible, which brings me to my next question.

If finding a stock piece is a challenge, has anyone bolted on a set of headers to a 325ix? I wouldn't be doing it for any performance increase, more so from the idea that it would be easier to fab an exhaust from the collectors back on a set of long tubes.

Your input is appreciated!

[downforce22]

my ix has some headers, but the previous owner installed them and exhaust that goes with it. Not sure as I have never owned/ examined a stock i exhaust.

[iXe<30]

my ix has some headers, but the previous owner installed them and exhaust that goes with it. Not sure as I have never owned/ examined a stock i exhaust.

Do you know which headers you have? Are there any clearance issues with them?

[downforce22]

not sure what I have, but it does not have the stock catalytic converter/ exhaust system.

[Kershaw]

yes it is most definitely different. the exhaust manifolds are the same, but everything from the manifold to the cat back is different. it curves over farther to clear the transfercase.

if you dont have any exhaust at all, i'd start with some ebay exhaust manifolds (do some research to get completely not shit ones) and have an exhaust shop make something for you. single pipe, 2.5" all the way back, shouldnt be too expensive.

[pawi30]

This may not help much but the part numbers are:


On REAL OEM the same picture is used for both.
1989 325iX : 11761716748

1989 325i : 11761716743

[Morrison]

I replaced everything from the manifolds back last year. I used an OEM BMW non-cat front section (European). You'll have to do some research on realoem.com to figure out the part number. Just watch out, cause they had a 3-piece non-cat exhaust system in addition to the 2 piece. The three-piece system won't mount up to a conventional US rear section though.
I chose to go with an Ebay stainless steel system for the back @ $180.

I think I paid just a little over $400 for the front section from DDM tuning, but you should also price it at www.bmwmercedesparts.com and see that they offer.

Interestingly, the front section is the exact same part number for both i and ix, but has a clamp that you bolt onto the pipes in the spot you need it to mate with the bracket on the transfercase.

[eugeman]

I replaced everything from the manifolds back last year. I used an OEM BMW non-cat front section (European). You'll have to do some research on realoem.com to figure out the part number. Just watch out, cause they had a 3-piece non-cat exhaust system in addition to the 2 piece. The three-piece system won't mount up to a conventional US rear section though.
I chose to go with an Ebay stainless steel system for the back @ $180.

I think I paid just a little over $400 for the front section from DDM tuning, but you should also price it at www.bmwmercedesparts.com and see that they offer.

Interestingly, the front section is the exact same part number for both i and ix, but has a clamp that you bolt onto the pipes in the spot you need it to mate with the bracket on the transfercase.

Excellent response - thank you very much .
Good to know that there are other factory options other than the original cat section.

[Morrison]

Oh, I also forgot to add that the european front section I received didn't have a bung welded on for the O2 sensor. This was solved for $25 at the local auto shop though. Granted it's only reading from one of the two pipes, but it's been running just fine this way for 8 months.