agent75 37 Report post Posted February 13, 2017 Hi all I am in full swing with my engine swap on the manual 330i that i picked up almost a year ago for 2k. I just realised that the 530i manifolds with integral cats on my "new" engine won't do for the E46 so was checking out the manifolds off the E46 blown engine. When this engine did what it did when it stopped going this appeared to involve a fair bit of oily residue in the exhaust to the point where i doubt the cat is in good nick. I can even see a black stain on the downstream side of the rear manifold cat suggesting oil getting sucked through it. I've done some word searches on the forum with no satisfactory answers but thought of some options - a. remove cats from factory, wierdy shaped but obviously decent flowing, manifold and weld in section of pipe (do i deserve to be drawn and quartered?) this car only has pre cat O2 sensors so sweet as there b. Where do I buy new cats, do they install those in old manifolds or am i talking getting my wallet removed via my ar*ehole for an entire new manifold? C. get some second hand manifolds and try my luck with some old, possibly worse for the environment than having no cat, cats ... meowww Quote Share this post Link to post Share on other sites
Rubix 434 Report post Posted February 13, 2017 I'm not sure with BMW's but could you gut the cats? I did this on my TT 300zx. If you have pre-cat o2 sensors I couldn't see the above being a problem, and you shouldn't have issues with legality (being that the cats are still there). Quote Share this post Link to post Share on other sites
Olaf 3317 Report post Posted February 14, 2017 yeah, Toluene's good for us all! Second helping please! (Toluene is a carcinogen). Always a top idea to eliminate the factory systems that catalyse harmful gasses into inert ones, gives one equal opportunity to poison your neighbours/family/friends/without them knowing it. Win! Please, take the road less travelled. Keep your catalytic converters intact - find a solution. Rather disturbingly, I'd be less disturbed if you were discussing disembowling cats, though of course that would still disturb me. 1 Quote Share this post Link to post Share on other sites
agent75 37 Report post Posted February 14, 2017 I constantly walk that line between loving fossil fuel based hobbies and self flagellation for loving fossil fuel based hobbies. i do agree with you but also have to bare in mind that a 16 year old 3 litre luxury car with cats that are likely doing more harm than good is not a good place to start for getting my green wings. I am going to have a chat to the guy i bought the engine from to see if he has anything... or if anyone on here has anything .. but the front cats are toast in my opinion and i ain't buying a brand new manifold and cats!. There is still what look like more cats further down the system so my green credentials are hanging on by a thread if i remove....and then two silencers after that and then some fancy looking valve thingy in one of the tail pipe tips. Fancy Germans. On another front my manual says M54 has post cat o2 but cant find anywhere... I don't think it has any. Its South African import. anyone else have a 2001 E46 with M54b30 who can shed light? Quote Share this post Link to post Share on other sites
agent75 37 Report post Posted February 14, 2017 11 hours ago, Rubix said: I'm not sure with BMW's but could you gut the cats? I did this on my TT 300zx. If you have pre-cat o2 sensors I couldn't see the above being a problem, and you shouldn't have issues with legality (being that the cats are still there). I guess i could do that, I know it's still eco terrorism but a 2001 car will still be legal if de catted (spayed?) Quote Share this post Link to post Share on other sites
Eagle 1662 Report post Posted February 14, 2017 I don't know easy it would be getting a 2nd hand manifold or if there are another options that can suit (sure members here the would know). I would just hollow out the cats myself if i couldnt get a easy\cheap replacement. In my experience people usually gut\replace the cat to sell and then sell the exhaust system anyway (may be different in this case having them part of the manifold) If you run your VIN number for build options and have the EU2 emission std then you probably wont have post cat o2 sensors. Quote Share this post Link to post Share on other sites
Olaf 3317 Report post Posted February 14, 2017 2. Have you contacted specialist BMW wreckers e.g. Brent at BM World or Ray at HellBM? To see if you can get good used parts? 1. More importantly, have you correctly diagnosed that your current cats are well and truly beyond saving? 3. Have you investigated what OEM/aftermarket/performance options are available? In NZ from one of our forum sponsors, or from abroad? Quote Share this post Link to post Share on other sites
agent75 37 Report post Posted February 15, 2017 21 hours ago, Olaf said: 2. Have you contacted specialist BMW wreckers e.g. Brent at BM World or Ray at HellBM? To see if you can get good used parts? 1. More importantly, have you correctly diagnosed that your current cats are well and truly beyond saving? 3. Have you investigated what OEM/aftermarket/performance options are available? In NZ from one of our forum sponsors, or from abroad? 2. i know the Auckland guys are well thought of but I'm in CHCH and will call our local Eurorec... I got the engine from them and they seen like sound guys 1. very likely f#cked. I'm not going to arse around fitting them for the time of it - the upper manifold looks like the funnel on a steamship which has been dipped in used engine oil 3. I'll check it out but may be overcome by GPS (gorse pocket syndrome) 1 Quote Share this post Link to post Share on other sites
Olaf 3317 Report post Posted February 15, 2017 Gorse Pocket Syndrome - loving it! Quote Share this post Link to post Share on other sites