Exhaust Manifold and Thermal Reactors

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adika
Posts: 2
Joined: Sun Oct 27, 2019 10:10 pm

Exhaust Manifold and Thermal Reactors

Post by adika » Thu Nov 07, 2019 10:43 pm

Hello,

I am from Canada and recently bought a '77 530i which is gonna need some work to be on the road. It has a hole in the exhaust manifold but I was wondering where I could find a new one since its pretty rusted. Also I am unsure if it has thermal reactors, but if it does how would i be able to remove them? Appreciate any help

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maybeillbuyit
Posts: 185
Joined: Mon Feb 17, 2014 12:26 am
Location: Vancouver BC

Re: Exhaust Manifold and Thermal Reactors

Post by maybeillbuyit » Fri Nov 08, 2019 11:58 am

Welcome to the forum. Where in Canada are you? Take a look at my project posting. I have a 77 and removed the thermal reactors. Theres a pic of what they look like VS the regular exhaust manifolds . There is also a post in the FAQs on removing all the EGR stuff that is part of the thermal reactor nightmare. Post some pics of your car :D
1977 530i another project
1979 635csi Euro "project"
1987 635csi

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528i-1981
Posts: 208
Joined: Wed Feb 07, 2018 5:50 am
Location: Boston North Shore, MA

Re: Exhaust Manifold and Thermal Reactors

Post by 528i-1981 » Sat Nov 09, 2019 8:18 am

Yes, Adika, welcome. BTW, Maybeillbuyit's project posting is in the Gallery, which you'll see on the board index if you back out of the Tech Forum. If you don't go with headers to replace the reactors, you have a couple of options with manifolds. The later E12 528i manifold (single 2" pipe) will work, and is likely the easiest replacement. I see them on eBay from time to time. Others have used E3 Bavaria or certain E28 manifolds from M30s, with some work needed on the downpipes or connectors (these are 6 into 2 systems with 1.5" pipes). I think somebody active on this board (Mike W., maybe?) used E28 manifolds on his E12.

Is the rest of your exhaust system usable? Are you doing this yourself or having a shop help you? Where you live will you be able to register it without the reactors or a cat?

What's great about E12s is you almost always have a couple of options if you're interested in doing some investigation, legwork and wrenching.

-Eric
(oo=00=oo) Eric
1981 528i Manual

adika
Posts: 2
Joined: Sun Oct 27, 2019 10:10 pm

Re: Exhaust Manifold and Thermal Reactors

Post by adika » Sat Nov 16, 2019 8:09 pm

Hello again, I am actually from Ontario. I will be posting pics soon just been working on it quite a bit. I plan on soign it myself so whatever will be easiest and cheapest lol. headers would probably be a nicer option but not sure. What headers would bolt right in? I am just starting with all this car stuff so bear with me. Thanks for the help.

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maybeillbuyit
Posts: 185
Joined: Mon Feb 17, 2014 12:26 am
Location: Vancouver BC

Re: Exhaust Manifold and Thermal Reactors

Post by maybeillbuyit » Sat Nov 16, 2019 9:30 pm

I don't know much about headers, I've heard some of them don't fit well and then you have to pay someone to weld to connect to the rest of your system. Personally I like BMW exhaust systems. Theres used stuff out there and I think all the mufflers for these cars are available new. Not cheap but hey'll last forever and bolt and unbolt so you can work on things. And good for you for doing this "car stuff" and not knowing what your doing. I was there a few years ago, another 100 years and I may know what I'm doing :oops: . Keep asking questions. Also search through the forum or internet, lots of people have done what your doing and have documented it
1977 530i another project
1979 635csi Euro "project"
1987 635csi

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