e36 M3 cat mid section exhaust on a e30

[1991318is]

Hey, i'm having a M50 swap into my e30. I would like to use the catalytic's of a e36 M3. This is a complete piece from front downpipes to rear resonators before the muffler. Has anyone had the experience of installing or heard any info on how to install and what modification's to apply. I know that it will fit with few measurements and some welding but still will like to get your help.

[Bryson]

it fits, if you're lowered you'll most likely scrape it everywhere

I don't know what you're really asking for, just have it welded in by an exhaust shop if you can't weld..
edit: the downpipes themselves won't fit without modification or special CABs (treehouse) that give you very excessive caster

[bmwe3]

i have the e36 s50 cat on my e30m3 s50 its very low no scraping yet but it sits low cut and weld

[Brew]

edit: the downpipes themselves won't fit without modification or special CABs (treehouse) that give you very excessive caster

I don't know if "excessive" is the right word. They are just m3 geometry AFAIK.

[1991318is]

Thanks guy's. If anyone alse has any suggestions please feel free to discuss. I am getting a good deal on this mint piece and i know that it's high flow. I'm not really worried about cutting and welding it's part of my project. But what i'm worried about now that i haven't thought about is the rubbing since my car is lowered. I guess i will need to make supports to keep it high enought as much as i can. I have a few questions for bmwe3, how low is your car, what spring's do you use, how's the sound and performance. What do you guy's think is it worth it or is there anything alse out there better or equal for about 300$. I would of went straight pipes with resonators, but i'm not crazy about poluting the air so i want to use a high flow catalytic.

[JasonH]

I have the same (E36 M3) center section on my car. A buddy and I cut and realigned the down pipes, in part, so flanges could be welded in at the base of the down pipe. This was done so the entire exhaust would not have to be removed if I have to do work under the car. At the back, stock center section flanges were welded on so that it would mate up to the rear. Since I got the center section for free, it made for an economical way to get my car back on the road after the swap. Also, the fact that they were designed for the M3 made me feel a bit more confident that I wasn't restricting exhaust flow (although the E36 325 center sections look to be the same as the M3). The combination of the M3 center section and a stock muffler or a Stromung (I've used both) results in a nice exhaust tone. Quiet at idle and low RPMs, but it opens up nicely at WOT.

That said, I wouldn't go this route again. The cats ride too low and the O2 sensor port is in a bad spot. If you are going to spend the money on an aftermarket "cat-back" system, then my recommendation would be to have an entire exhaust system fabricated. It likely wouldn't run you much more (especially if you are spending $300 on the center section). Buy and aftermarket cat and muffler and have a good exhaust shop weld up the pipes. Just make sure they don't weld the ENTIRE exhaust system together.

[Bryson]

edit: the downpipes themselves won't fit without modification or special CABs (treehouse) that give you very excessive caster

I don't know if "excessive" is the right word. They are just m3 geometry AFAIK.

they're not e30 m3 geometry. I just put a set on my old 318is two weeks ago, set them next to e30 m3 bushings, they're ~3mm farther offset. I was told repeatedly (even by treehouse) that they were e30 m3 offset though :roll: Doesn't change the fact that I think they're a great product and would recommend them for someone with an e36 5 lug swap.

[Brew]

edit: the downpipes themselves won't fit without modification or special CABs (treehouse) that give you very excessive caster

I don't know if "excessive" is the right word. They are just m3 geometry AFAIK.

they're not e30 m3 geometry. I just put a set on my old 318is two weeks ago, set them next to e30 m3 bushings, they're ~3mm farther offset. I was told repeatedly (even by treehouse) that they were e30 m3 offset though :roll: Doesn't change the fact that I think they're a great product and would recommend them for someone with an e36 5 lug swap.

Interesting....

I agree that they are a great product, although I don't know if I would go the same route again if I was building a mainly street-driven car. Coupled with GC 350/475 and Koni's, the ride is harsh. I can't imagine how it would be with 17s and rubber band tires.

[trent]

edit: the downpipes themselves won't fit without modification or special CABs (treehouse) that give you very excessive caster

I don't know if "excessive" is the right word. They are just m3 geometry AFAIK.

they're not e30 m3 geometry. I just put a set on my old 318is two weeks ago, set them next to e30 m3 bushings, they're ~3mm farther offset. I was told repeatedly (even by treehouse) that they were e30 m3 offset though :roll: Doesn't change the fact that I think they're a great product and would recommend them for someone with an e36 5 lug swap.

This is true. I was the one that found this out and showed Bryson. I am worried about the extra caster these will provide. To much caster creates a large weight shift.

[trent]

Sorry for the hijack, I took some of this talk about caster and posted it here,

http://www.r3vlimited.com/phpBB2/viewtopic.php?p=209834

[1991318is]

I did'int think i would get such feedback on this subject. I'm glad, someone alway's reply's to my topic amazing web site. Thanks again. How much would you spend for a e36 M3 cat mid section exhaust in excelent condition. I know i said that i was getting it for 300$ but i told him that i was'int to shure about buying it and now his willing to drop the price. It just sounds to me crazy putting this in my car with the m50, i kind of like that, for shure it will require a lot of work but that's what make's it a interesting project. I know that it will sit low as long as it does'int rub when i hit bad streets or go down or up on driveway's to enter in a garage. JasonH what suspension do you ride on or how lowered is your car, have you had any hit's on your exhaust. You are probably right about getting after market but how much do you think would i end up spending one's all done with 2 cat's and 2 resonators, oxygene sensor, piping. And will it be same or greater quality or sound compare to the original bmw part e36 M3.

[Beau B]

I was going to get a custom exhaust for my S50, but decided for the time being to just use the S50 midsection as well. Teckmark, a race team that races in Speedvision Touring against Turner was going to do it for me. They quoted me under $1000, but closer to $800. But that was for a 3 inch header back with a single cat, and a Borla muffler.

Beau

[ed94r]

Are you required by law to have a cat? Better question, are there sniffer tests in your area? We don't have sniffers in VA (yet) so I just ran medium sized resonator in the place of the cat. Saved alot of weight by not using the factory E36 cat. Just have them weld it up tight -I had to have them do it twice- and there should be no ground clearance issues. I ended up using 2.5" pipe w/ a Simonz resonator and an Edelbrock straight thru muffler. Just a tad louder the my stock old M20 stuff.

The muffler shop costs me $250. I bought the muffler new ($80)and the res slightly used ($20).

[1991318is]

Thanks again for the great feedback. The guy selling this is willing to let it go for about 185$ US wich i find it's a great deal. I just love having two separate pipes and catalytic's, better flow and since i'll be using the cat's enviroment friendly less polution. I dont mind the cutting and welding.
:P

[Ryan Stewart]

I was going to get a custom exhaust for my S50, but decided for the time being to just use the S50 midsection as well. Teckmark, a race team that races in Speedvision Touring against Turner was going to do it for me. They quoted me under $1000, but closer to $800. But that was for a 3 inch header back with a single cat, and a Borla muffler.

Beau

This is similar to what I am running. I just dont have a cat, an XR1 resonator takes its place. Im thinking of a cat though, the thicker walls and backpressure would quiet the exhaust up bunches (in the car).