E36 Header: Anything worthwhile?

[Fair]

Question to you track/auto-x guys out there that have semi- or daily driven E36 M3's. Is there a good, proven header design that is still OBD-II compliant? (air injection) If so, what are the dyno increases, if any?

After looking at the common Chinese/eBay junk, SuperSprint, and the Euro M3 headers (no air injection), I haven't seen anything that looks worth doing and/or legal for our use. They all seem to make big compromises trying to hook up to the factory header-back exhaust, or for ease of manufacture. The power gains I've seen boasted about are in the "dyno resolution" range (meaning: small).

We run a '97 E36 M3 in a class that must retain emissions/air injection and a catalyst, not necessarily the stock converters or exact location though. Trying everything possible to make up a 100+ hp deficit to AWD turbo cars in our class. There's 100 hp in the exhaust, right?? :D (joking!) The factory header looks OK for a stock piece but is still pretty compromised by racing standards. The ECM can be tuned to maximize any gains in our class, if needed. A mid to high rpm power boost of 15+ hp is what we're looking for. A completely custom cat-back is allowed.

If there isn't an off-the-shelf option that works we will look at doing a custom stainless header and header-back exhaust for this application. Something with a longer primary length than stock, fewer kinks/bends than the Euro header/others, and a single 3" collector instead of the 2 smallish factory ones.

Would this be worthwhile to people with track/street/auto-x M3s: An emissions legal header/exhaust that might actually make power?

edit: we know that going from 2 to 1 collectors/cats wouldn't necessarily pass California CARB compliance, but that isn't the goal.

[vjlax18]

You'll hear all sorts of answers/opinions on this one. I was told stock OBD-II on anything without cams/work. Track cars should use KK or Euro and street cars should use the Remus headers. Anything other then stock listed have no ports for the Air pump. However, you could always just get the AA sim and leave everything in there, just unplug it.

[Fair]

You'll hear all sorts of answers/opinions on this one. I was told stock OBD-II on anything without cams/work. Track cars should use KK or Euro and street cars should use the Remus headers. Anything other then stock listed have no ports for the Air pump. However, you could always just get the AA sim and leave everything in there, just unplug it.
The headers have to have the air injection ports to be legal for the class we run in. It wouldn't even pass a visual inspection this way...

[VahramHS]

The headers have to have the air injection ports to be legal for the class we run in. It wouldn't even pass a visual inspection this way...

Supersprint Euro 3.2s, ask Erik @ Edge how much power our racecar made with just adding those.

[John in Houston]

The headers have to have the air injection ports to be legal for the class we run in. It wouldn't even pass a visual inspection this way...


Dude, you have a drill and a welder... get some Euros and go to work.

[vjlax18]

:lol Actually, yeah, it's just 2 holes and 4 grooves.

[Erik L]

ummmm guessing he thought of this.

[vjlax18]

I was laughing at John and myself. I've welded up the ports before, I just never thought of grinding them out to keep the emissions equipment.

[John in Houston]

I was laughing at John and myself. I've welded up the ports before, I just never thought of grinding them out to keep the emissions equipment.


Actually, you only need to drill 2 holes... and no groves. The O2 sensor is far enough downstream that by injecting air into just one primary pretty much handles it.

of course, you could drill 6 holes and just run tubing to each one... but that's just too much work for a lazy bastige like me.

Oh yeah... and never underestimate Fair... he misses some things :D

[Fair]

ummmm guessing he thought of this.
Yea, I thought of this. Just haven't seen any substantial gains from the Euro M3 header, and it still looked pretty compromised.

Remember - I need a 100 hp gain here! :lol

[John in Houston]

Yea, I thought of this. Just haven't seen any substantial gains from the Euro M3 header, and it still looked pretty compromised.

Well... you know I never had access to a dyno ;)... so my numbers probably wouldn't mean anything to you (3.2 Euro headers).

:lol

[Fair]

Well... you know I never had access to a dyno ;)... so my numbers probably wouldn't mean anything to you (3.2 Euro headers).
Did you dyno with those? What were the numbers Mr. Smartee Pants. :)

[John in Houston]

Did you dyno with those? What were the numbers Mr. Smartee Pants. :)

I'd post them here, but I'd be called a liar.

Lets just say that the low end did not suffer NEAR as much as everyone lets on. The top end was more than enough and good for auto-x shituations (higher RPM range).

I'll IM your girlfriend the numbers ;)

[Fair]

I'd post them here, but I'd be called a liar.

Lets just say that the low end did not suffer NEAR as much as everyone lets on. The top end was more than enough and good for auto-x shituations (higher RPM range).
After hearing the numbers you gained from the (crap) Euro M3 headers I am a bit more enthusiastic about what a less kinked and compromised design will make. Hmm... will have our fabricator give the M3 a closer look today.

[hairless ape]

SuperSprint Euro Race FTMFW

[Fair]

SuperSprint Euro Race FTMFW

Thanks for the response.

Link to Prices (http://www.vacmotorsports.com/cgi-bin/view_item.pl?cat=Exhaust) - Link to Picture (http://www.vacmotorsports.com/db/images/ss-e36-large.jpg)

SuperSprint Euro Exhaust System (pictured above... maybe?) $1409 for header (not emissions legal), center section is $475 (no cats), muffler is another $750-820. Total exhaust system, no cats, no OBD-ii provisions = $2707. What power increase is there? It looks pretty compromised near the collectors; primaries are short, muffler/header-back exhaust looks big and heavy. A race worthy exhaust could lop a lot of pounds off of that and still be emissions legal.

http://www.hmsmotorsport.com/ximg/2105/785501.jpg

Another Link (http://www.hmsmotorsport.com/store/supersprint/e36-exh/e36-325-exh) - don't know if this is the same header (its a SuperSprint but looks different). I'm just not too excited about SuperSprint... they make street car-like exhaust (DTM tips yo! sheesh...) but the header looks compromised and none of it is emissions legal or have provisions for OBD-ii bits ('96-99 M3). Can't find any data on gains other than some "7 hp" claims.

[TYE]

www.jpperformancellc.com

Give them a call and ask for Jose, he knows his stuff.

This is what Im running:
http://i97.photobucket.com/albums/l223/bmwtye/bmwe36longtube1.jpg

33" long step down header.

I was originally running his shorty headers and noticed nice gains with them as well, so thats another option.

[Fair]

Hey, that's more like it, Tye. Thanks for the tip. Any dyno proven gains from going to that header? Cost estimates? I will call Jose... he might not want that info posted yet.

Keep 'em coming, guys! :)

[hairless ape]

Terry, that is the SS Euro, not the SS Euro long-tube race, IIRC

To be specific, this is what I meant:

http://www.supersprintna.com/product-exec/product_id/1553/category_id/140/search_make/1/search_year/1997/search_model/143

http://www.supersprintna.com/product-exec/product_id/1510/category_id/140/search_make/1/search_year/1997/search_model/143

http://www.supersprintna.com/product-exec/product_id/1509/category_id/140/search_make/1/search_year/1997/search_model/143

[ScotcH]

If you're looking at teh SS, might as well get the knock-off for a fraction of the cost. It LOOKS just as good :)

[vodomagoo]

I have knock off euro super sprints and have decent gains but much better gains can be had with smaller primaries better suited for u.s. heads imo. KromerKraft might be able to set you up with something that might work better then the euro ss or even take euro oem headers to a builder and see if he can improve them.

[Mad Dog 20/20]

Call Kromer. He'll fab whatever you want in whatever material you want. I'm sure he can put some air injection ports in a couple of the primaries and add 02 bungs if you want. Or you can DIY it.

I'm running his 6-2-1 system on the street with 02 bungs added and injection sims. Just had to lengthen one 02 sensor wire and do a little welding (bungs).

The car rips and sounds amazing.

http://forums.bimmerforums.com/forum/showthread.php?t=725279&highlight=kromer

The engineering is second to none. All 6 primaries are truly equal length and stepped, as well as the correct size for our little exhaust ports. The collectors are works of art with a very gradual/seamless merge and a "tower" in the middle to limit turbulence. Very nice stuff.

[hairless ape]

Garrett, reading that thread is very interesting. My car is technically obd2 as well. I just installed the SS euro full-race exhaust bought used from a friend. The headers do not have O2 ports (I don't care since the car is now track only) and I expected to have the CEL permanently on. However after a weekend track test where I put 280 track miles on it, there was no CEL.

[Jonathan@BimmerWorld]

However after a weekend track test where I put 280 track miles on it, there was no CEL.

Does it light up during start up? I'd almost guess the bulb to be out.

[hairless ape]

Yes it does. CEL works just fine. Pre-cat O2 sensors are installed in the SS collectors. Post cat O2 spoofers remain from my previous AA crack pipe.

[GotCone?]

I'm going on the cheap for just a little improvement. Stock S50 manifolds, but port matched to the stock gaskets and contouring the inlets and polishing as far in as I can get. Since I have '95... it's a stock manifold so no worries there for the air pump stuff. Same approach could be made to the '96-99 manifolds as long as they are cast and have room for the work.

IMHO... for the money good designed and tested/proven headers cost, I don't think it's worth the money for ST* since the bigger gains will be when one can do cams, head work, etc. Weight savings would be the only real advantage, assuming they don't actually hurt performance.


Jon

[Mad Dog 20/20]

Garrett, reading that thread is very interesting. My car is technically obd2 as well. I just installed the SS euro full-race exhaust bought used from a friend. The headers do not have O2 ports (I don't care since the car is now track only) and I expected to have the CEL permanently on. However after a weekend track test where I put 280 track miles on it, there was no CEL.

The lack of a CEL is quite odd. It can take a while sometimes. 280 track miles is certainly more than a while, though.

When I first got aftermarket headers and ripped-out the hair-dryer (years ago), I got a CEL within the first week.

The only thing I can imagine is that your mixture is WAY lean and the computer is mistaking this for air injection during start-up. But then, one would expect a CEL during normal operation. Very weird.

[GotBHP?]

The lack of a CEL is quite odd. It can take a while sometimes. 280 track miles is certainly more than a while, though.

When I first got aftermarket headers and ripped-out the hair-dryer (years ago), I got a CEL within the first week.

The only thing I can imagine is that your mixture is WAY lean and the computer is mistaking this for air injection during start-up. But then, one would expect a CEL during normal operation. Very weird.

The CEL for the air pump is triggered by a certain number of cold starts IIRC from all the troubleshooting I did when I installed the euro SS headers.

One other thing to look out for on the Euros if anyone has one is that the pre-cat O2 sensors on the car aren't long enough to reach the exhaust stream without grinding down the threaded bungs on the collectors. Supersprint might have corrected that by now, but it sure gave me a ton of headaches trying to track that one down..

[Mad Dog 20/20]

The AA air pump sim taps into the 02 sensor wires. So I assumed the ecu is looking for a certain afr range at cold start-up to confirm that adequate air is being injected. I too think it takes a certain number of "out of spec" cold starts for the CEL to trigger.

[hairless ape]

I would not be surprised that it might be lean. Headers tend to lean out a car like this anyway, I am told, despite adaptable ECU's. My plan is to add an M50 manifold and Samco boot, then dyno with AFR, and then have my favorite vendor make me a flash to set me up properly to fix what will probably be a lean AFR.

[JamesM3M5]

I believe the air pump is run briefly once the system is up to temp to test the air injection. The upstream sensors will detect a super-lean mix for a brief second and that tells the OBD2 monitors that everything is OK.

And yes, I modded a set of Supersprint US headers to accept a smog pump injection pipe. Was pretty damn easy, too. I doubt you'll see a huge power gain with the SS headers for US cars, but hey, a gain is a gain. If cost is no object, then custom is the way to go.

A good racing cat won't lose any power if installed well. So if your class requires a cat, get a Random Technology metal matrix unit and some long cones to weld up to the inlet. It will take a bit of modification to the RT cat, but it's worth it.