Question for members with Stahl headers

the stock e9 exhaust has two pipes going into the center resonator and then exit into one pipe. the coupeking exhaust combines into 1 pipe before the center resonator. with the stahl header and the coupeking exhaust you have to fabricate a 'Y' connector between the 2 systems. with systems like fritz's bits it is similar to the stock system, just more free flowing

[Broken External Image]:http://www.fritzsbits.co.uk/images/stories/virtuemart/product/3.0CSL_centre.jpg
 
the stock e9 exhaust has two pipes going into the center resonator and then exit into one pipe. the coupeking exhaust combines into 1 pipe before the center resonator. with the stahl header and the coupeking exhaust you have to fabricate a 'Y' connector between the 2 systems. with systems like fritz's bits it is similar to the stock system, just more free flowing

Funny I was looking at Fritz last night. My thought about the H-pipe was that you could do it on the two pipes leading into the exhaust. That would give you the cross flow without having to weld your downpipes together.
 
Funny I was looking at Fritz last night. My thought about the H-pipe was that you could do it on the two pipes leading into the exhaust. That would give you the cross flow without having to weld your downpipes together.
that was what i was thinking of using ... and exactly why i was thinking of an H pipe for the bung. but, since they co-mingle inside the radiator, you don't need the H pipe. so i will just put a bung on one of the tubes.
 
Mark,
Not sure this is relevant anymore, but I am a few steps away from my Stahl header (and the engine/car it is attached to). If you'd like me to look at/measure anything, let me know. I can do it tonight or tomorrow morning.
 
Mark,
Not sure this is relevant anymore, but I am a few steps away from my Stahl header (and the engine/car it is attached to). If you'd like me to look at/measure anything, let me know. I can do it tonight or tomorrow morning.

Yes Please! I think I'm going to add a bung on each collector. Figure that your typical 02 is about 1.5" to 2" long. Can you check to see if I mount the 02 between 10PM and 2PM on the "roof" of the collector, will it clear the floorboard? Thank you Stephen!
 
STick a single O2 sensor on the Y-pipe like on here:

exhaust1-jpg.6394
 
STick a single O2 sensor on the Y-pipe like on here:

Hi aaron,

I’m not sure if that was a recommendation for me or in general. A perfect spot in general but I don’t have a Y-pipe. Each header goes directly into the muffler.
 
Okay, this experiment doesn't look as pretty as I'd hoped. It really highlights how rusty the headers are and how crusty the car is. But on with the O2 sensor mock-up. The first three photos are taken to illustrate just how "long" the Stahl long pipe headers are. The primaries extend down all the way to the underside of the car and travel some distance before collecting. And the first collector is pretty far forward of the second collector, presumably maintaining equal length primaries or there about.
20180208-side view-01.jpg


20180208-side view-02.jpg


20180208-side view-03.jpg


These last two photos are looking down the tunnel from the rear of the car. The mock O2 sensors are 2 1/2" long screws held on by some double sided tape. I was able to get the sensors facing almost vertical: 11 and 1. They fit in that orientation way, but my tape sagged before I could get the camera in place to snap the pics. I believe they are clear of all obstructions with a comfortable clearance.
20180208-from rear-01.jpg


20180208-from rear-02.jpg

And I think the rear sensor location (on the right) probably wants to be slightly further back. Seems there is a bit more room there, plus that would place the bung closer to the same distance back from the collector as the other group. Let me know if this is legible.
 
This is perfect Stephen! I think that to your point as well, it illustrates what is going on with Stahls, and their massive length.
 
If this is the information/solution you were looking for, I can measure from the ends (or the collectors) the zone where the bungs should work.
 
If this is the information/solution you were looking for, I can measure from the ends (or the collectors) the zone where the bungs should work.

Hi Stephen,

That would be great! The measurements starting from the weld that joins the collector to the downstream exhaust pipe would be perfect.
 
Funny how the second time I locate the mock-up O2 sensors, they didn't seem as carefree as the first go around. Plus, the car is on dollies, pushed up against the garage wall. I had to pull it away from the wall to get to the exhaust side. Used a nylon ratchet strap between the dollies and the wheel of the M3. But I was too lazy to jack the car up off the dollies - so it was a tight fit with me laying between the wall and the car, half squeezed under it. :confused:

But I think I was able to get pretty good locations for the O2 sensors, and I pulled some measurements from the mock-up to document. See below:
20180208-bung locations.jpg
20180208-inner bung orientation.jpg
20180208-outer bung orientation.jpg
 
Just wanted to clarify that the length dimensions I noted were not "as the crow flies". Rather, they are the distance that follows the centerline of the secondary pipe. Another solution that would be similar to the placement I plan on doing with the "Y" pipe is to locate the sensors closer to the horizon - about 2 or 2:30. They can probably be at the exact same angle then, which would "look" a little more polished compared to the different directions of closer to vertical axis. You mentioned you'll only be using one sensor so this might be irrelevant.
 
Thanks Stephen! I’ll use your dimensions. I’ll probably be a little conservative with the angle and go more towards 2PM. I don’t plan to drop off the headers until next week. I have a bit of time to fiddle.
 
Stephen, you need to degrease your gear box . :p
Yes, that's one of a long list of tasks. I'll probably save that one for when I pull (or drop) it out.

I’ll probably be a little conservative with the angle and go more towards 2PM.
I think that should work. My 2.5" long mock sensors began to get close to either the bottom of the tunnel (for the inner pipe) or the bracket on the transmission (for the outer pipe) as I rotated them down. But the actual sensors will hopefully be shorter and give you more freedom. Also, not sure which trans you have. Mine is a 265, so it has the extra case section and is longer. The original trans would be shorter, and would create different opportunities I assume.

Be sure you have room to get a wrench on them if they need to be removed.
Indeed. There seems to be a lot of space immediately around the pipes. I would think the right tool would easily access the sensors.
 
Back
Top