E30 Zone

I'm looking to change the backbox on my 325 non cat system at the weekend and would like to know what bits I should replace while I'm about it. Obviously I have the new exhaust but what about clamps, gaskets, bolts etc. In particular the join between backbox and centre appears to have an o-ring gasket on each pipe - I assume these are going to be knacked, are they easily available?

All new nuts and bolts should be used as a matter of course, and all well coated with copper grease.
Whether or not the clamps around the box need replacing, depends on their condition, and whether they fit your new box.
I've never renewed an O ring yet!
Rear boxes tend to rust where the clamp fits, so, on new boxes, I fit a layer of exhaust bandage (the stuff intended for patching up the holes on the likes of three year old Fords) between the clamp and the box.
Haven't been doing it for enough years for conclusive results, but the ones I've done seem to be not rusting.

You can get all the bits you need from cotswoldbmw put a post up on the genuine bmw parts section with what you need and they will quote you happy.

Brianmoooore wrote: Rear boxes tend to rust where the clamp fits, so, on new boxes, I fit a layer of exhaust bandage (the stuff intended for patching up the holes on the likes of three year old Fords) between the clamp and the box.
Haven't been doing it for enough years for conclusive results, but the ones I've done seem to be not rusting.

What a brilliant idea!! Something else to do to the 'folly' exhaust as it is finaly fitted up.

(the stuff intended for patching up the holes on the likes of three year old Fords)

LOL !!!

I replaced every mount and bracket ,just for my piece of mind,however the only parts that were showing signs of any possible failure were 1x rear silencer strap and the bracket that bolts under the g/box that clamps the pipes.
I to re-used the (metal) o-ring seals and they are still a perfect seal.