exhaust options

[Rev Engineer]

Could people chime in with the various exhaust systems they have gone with? I'm nearing the last step of my s50 conversion and need to decide on an exhaust system. I've read that a e36 m3 with a stromsong muffler works without too much difficulty. Seems like most people go full custom, but this sounds like an expensive route. Is there anything else that's common? I'd like to keep this thread open to everyone for future reference, but my specific criteria consist of:

- s50 with s52 headers - (should I cut and reweld the flange that's near the CAB?)
- don't care about having a cat but wouldn't object to having one
- would like it to be free-flowing (e30 325i exhaust wouldn't work)
- I'm not interested in having a loud muffler - something a little louder to moderately louder than stock is ok. I've heard this might require more than one muffler.

I'm open to having someone build a full custom exhaust if necessary, but I'd like to explore less expensive options first. Seeme like buying used e36 m3 exhaust parts and a new stromsung muffler might be a lot less than a full custom setup.

[rede30]

custon exhaust doesnt really mean more expensive, i have thought it to be less. headers to dull 2.5" pipes to a hallow cat to a ________ exhaust(probably stock e36 m3) is my plan and i belive that labor cost wont be to bad.

[equate975]

I had a full out custom with a single 2.5 made for about $550 with custom mid pipes. I think you can run a stock e36 exhaust. Your best bet if this is possible if to get an e36 exhaust and cut the mid pipe off and weld on a custom one from that back.

[FredK]

C ///M has S52 headers, OBD-II midpipe, and Stromung cat back exhaust. If you keep your stock CAB brackets you'll have to mod the downpipe to clear the brackets. If you run Treehouse Racing CABs you don't have to do any cutting / welding.

However, if you want to run an O2 sensor, I suppose that you'd have to weld in some kind of merge pipe so you can sample both front and rear banks of cylinders...

I guess the stock M3 exhaust doesn't work because the can is too big. That sort of puts a big dent in MY plans! :( I was planning on S52 headers, OBD-II midpipe, and stock M3 exhaust. I guess I'll have to see what happens. I think the can might be too big to clear the rear suspension or something.

Anyway, a Stromung costs a lot of $, new or used. I might have to get a cat back exhaust because of clearance issues, in which case I will most likely get a magnaflow with a fairly small can and weld it up to the stock M3 exhaust pipes. Or something like that. I could always just stick the M3 exhaust on my E36. :)

Here's the breakdown of my welfare exhaust:

S52 headers $100
OBD-II midpipe $175
M3 exhaust, may have to cut to salvage the pipes only $100
Magnaflow muffler $150

$375 to 525, depending on what I have to do.

[Rev Engineer]

I can handle $550 if that gets me a complete exhaust from the headers back. A couple friends estimated about $1k, which I think is too much.

I like the idea of using an obd-II midpipe, but the single o2 sensor poses a problem. What are the s52 obd-i people doing? I might guess that a single o2 sensor on one of the banks probably isn't that bad. Making a connection between the pipes probably hurts flow.

Since I can go without a cat, I'm leaning towards full custom if I can really get it done for around 500-600. If not, than the obd-ii midpipe with cats might be my next best option with custom back from there.

I didn't know the stromung exhaust was a spendy one, magnaflow is probably a better route then. Any comments on how loud a magnaflow might be? Should I consider two of them to keep this thing quite? I'm really not a fan of loud exhausts.

The stock e36 m3 muffler is totally out. The consensus is that it doesn't fit, and it's fricken heavy.

FredK – Are you planning on doing the entire exhaust yourself?

[DEV0 E30]

Any comments on how loud a magnaflow might be? Should I consider two of them to keep this thing quite? I'm really not a fan of loud exhausts.

I have dual 2.5" with magnaflow cats, and muffler and it's too loud, pretty much the loudest E30 around my area. I'm going to be changing it soon.

[FredK]

FredK – Are you planning on doing the entire exhaust yourself?

Probably. I'm going to try to borrow a friend's MIG welder. Hilarity should ensue.

I was thinking I might have to section out a piece of the OBD-II midpipe and weld in a prefab x-pipe and a O2 sensor bung, but I guess I'll get to it when my swap is more complete--i.e. more than just a collection of parts. :)

[02stu]

How restrictive are e30 325i exhaust's when used with an m50?
Thanks
-Stu

[Bennetts22@aol.com]

OK i did the s52 and used the stock headers.. we heated the back down pipe and bent it in about 1/4in so it would clear the sway bar.. the front down pipe we hade to make a custom pipe off the flange because of the control arm.. So i did dual pipes and made a x pipe right after the down pipe.. (fall-line told me this would make the sound deeper and make more power). So after the x pipe dauls into the stock 2 cats from a m3 e36 and then duals from their into the B&B triflow.. We had to do the exhaust 3 times before doing it this way and getting it right.. now is sounds sweet and nice and low with very little rasp.. the bill was 200 the first time but after redoing it 2 more times the grand total was 400.00 the car sound great!! If you do true dual and no x pipe the car will sound like a 80hp ricer. thats how it was the first time.. the chambers need to mix before the muffler.. so a xpipe / h pipe will give you the great sound and power.. also i used 2.5in pipe

[static]

i have a s50 swap, and for now i used the original cast iron headers; custom made section x2 2.25" going from headers Y'ed into a 2.5" pipe, mandrel bent all the way to an E36 M3 muffler, which was fit quite ncely with small amount of underbody massaging (had to cut off the original catback pipes from it). I have a flanged hiflow Magnaflo 2.5"cat, substituted with a trackpipe right now.

The setup is surprizingly not loud at all, but is not very pleasing either, untill i hit around 3.5-4rpm after which it sounds quite nice, but still not as nice as Stromung on a E36M3 in those understeer.com videos. i never really heard my car from the outside or taken any videos so don't know how it sounds from outside.

The E36M3 muffler is also VERY heavy, but i figured that it's a temporary solution and all the extra weight is down low and offsetting the extra weight introduced in the front with S50.

The custom exhaust + work + cat + trackpipe + muffler costed me around $1K, but i used SS piping so it'll last longer

My future plans are thermo-powdercoated ebay SS headers (for E36s), better Y section into the 2.5" pipe and a lighter freer flowing muffler.

Also my friend has S50 E30 running the biggest Magnaflo muffler that he could get to fit. At WOT his car sounds like shit! incredibly loud and raspy.

EDIT: here is a video of my setup

http://video.google.com/videoplay?docid=-7924058971022829659

Alex

[bdi_fc]

Added to DOHC Wiki. http://www.e30dohc.com/wiki/index.ph...Basics#Exhaust

Please update as necessary.

[dougsic]

I have stock s50 manifolds and e36 M3 exhaust back to the stock e30 325i muffler and it sucks. The shop that did the conversion beat the crap out of the front downpipe to get it to clear. The car has Treehouse cabs (nice product).

The e36 cats hit the underside of the car although I've twisted and turned them every which way. Even removed my heat shielding to no avail.

I wouldn't recommend this exhaust to anyone.

The shop that did the conversion assured they would do a custom exhaust that I'd be happy with but that didn't happen. They ripped me off in many ways - the exhaust was just one of them.

Here are the options I'm looking into.

TMS shorty headers - $800.
Supersprint headers - $1,200.
ebay headers - $250.

I'm going custom from the headers back once I decide which ones to get.

How did you guys with long tube headers clear the sway bar?

[325Projectz]

I did a full mandrel bent exhaust, ran me about $650. Muffler, cat, pipes & labor.

Added to DOHC Wiki. http://www.e30dohc.com/wiki/index.ph...Basics#Exhaust

Please update as necessary.

Nice, that little site is coming right along. :up:

[equate975]

I have stock s50 manifolds and e36 M3 exhaust back to the stock e30 325i muffler and it sucks. The shop that did the conversion beat the crap out of the front downpipe to get it to clear. The car has Treehouse cabs (nice product).

The e36 cats hit the underside of the car although I've twisted and turned them every which way. Even removed my heat shielding to no avail.

I wouldn't recommend this exhaust to anyone.

The shop that did the conversion assured they would do a custom exhaust that I'd be happy with but that didn't happen. They ripped me off in many ways - the exhaust was just one of them.

Here are the options I'm looking into.

TMS shorty headers - $800.
Supersprint headers - $1,200.
ebay headers - $250.

I'm going custom from the headers back once I decide which ones to get.

How did you guys with long tube headers clear the sway bar?

I think your shop did a terrible job then. The e36 exhaust will fit, its all about the down pipe though, if thats off then no exhaust will fit correctly.

[Mot]

Im running ebay headers to stock e30 midpipe/cat to stock e36m3 muffler. I also ran a Brullen e30 catback for a while. Both bolted up with no issues...