Project E36 323is: Building the Poor Man’s M3, Part 4 – Exhaust



E36 exhaust removal
Luckily, an exhaust swap on an E36 isn't the toughest job in the world, but it's much easier on a lift, so we were happy to hand the keys over to Howard Watanabe at Technosquare again.  The hardest part can be loosening the old exhaust bolts, since these cars aren't exactly young.  It's not a bad idea to go with fresh hardware and gaskets just to be safe, and plan on replacing your rubber hangers if that hasn't been done recently. 
Stock E36 323is center section
These are the stock 323is center section pipes coming down from the exhaust manifold.  Being OE parts, the M3/328i pipes don't look much different from this angle and they bolt right up.  They aren't light, however, so having a second person to help is highly recommended, since it also makes it easier to line everything up.
E36 M3 center section
As mentioned, the M3/328i dual-pipe center section bolts right up and looks factory… Because it is.
E36 323is single-pipe exhaust
A quick view of the former single-pipe going back to the old stock muffler section, now replaced with…
Corsa E36 exhaust
Dual pipes all the way from the exhaust manifolds through our new Corsa exhaust. You can almost see how good it sounds.


  1. This is really dope, but I have a question regarding the O2 sensors and wire harness.
    I know for the 323is exhaust there are only two O2 sensors. One before the cat and one after. but on the 328 exhaust theres a total of 4 because of the dual cat setup. Did you have to use the s52 wire harness for this setup? I did this exact same engine build on my 323is and im wondering if the s52 tune I have on my ecu will run properly with my standard 323is exhaust

    1. Curious to find out too about the o2 sensors. I am looking to do the same with m3/328 downpipe all the way to the muffler. Also wonder how much power gain in real world (0-60 time).

    2. I did this exhaust swap on my 323ic and now have an engine code P0133 after relocating the single pre cat sensor to one of the headers. I’m at my wits end and don’t know how to fix this issue without getting a whole new wiring harness for my car. Anyone else who’s got an idea of what to do please reply.

Leave a Reply

Your email address will not be published. Required fields are marked *