[TDIwyse]

http://www.realoem.com/bmw/showparts...15&hg=18&fg=10

Have been looking for a good deal on this for awhile to further some modifications. The realoem price is hugely inflated if you are patient and have time to wait... Finally found a good deal on a new unit, and bought it. Thought I'd share some details with the community.

It weighs just under 40 lbs.

The diameter of the opening (without the DEF "mixer") that mates to the DPF unit is just under 3" diameter with an outside pipe circumference of ~9.4". This is the minimum circumference of this entire section, and most likely the maximum restriction based on cross section area.

The pipe turns from round to oval shortly after the DPF connection. The diameter of this pipe up to the catalyst has a minimum circumference of ~10" at the input to the catalyst where the pipe then flares outward to meet the larger area of the catalyst.

Post catalyst the oval is quite large at ~ 13", then slowly necks down to the dual pipe connection where it is ~11.5" by the 2nd NOx probe/sensor.

The dual pipe sections are ~7.5" circumference everywhere except for one bend that necks down to ~7.25".

The combination of the dual path pipe, even with the neckdown point on the one side, seems quite sufficient and should not be the limitation in this section.

There may be some work coming along where there will be some interesting exhaust work done in conjunction with the Ecotune modifications...

If anyone is interested in some particular data/measurements related to this item before it becomes altered, please let me know. Otherwise it might be too late.

[JDG]

Awesome, thanks for doing this. Are you going to do a complete system whey you get a DP?

[BB_cuda]

haha, TDI i think you said diameter a couple times when you meant circumference. 7.25" diameter, that would be huge, right?

I have a tape called a "Pi" tape. It is a very flexible tape made for bending around not perfectly circular cross section. As you might guess, it is off by the factor Pi so that even though you are measuring around the circumference, the readout is diameter in inches as C=Pi*D. I think i got it from mcmaster carr about 10 years ago.

[TDIwyse]

Originally Posted by BB_cuda

haha, TDI i think you said diameter a couple times when you meant circumference. 7.25" diameter, that would be huge, right?

I have a tape called a "Pi" tape. It is a very flexible tape made for bending around not perfectly circular cross section. As you might guess, it is off by the factor Pi so that even though you are measuring around the circumference, the readout is diameter in inches as C=Pi*D. I think i got it from mcmaster carr about 10 years ago.

Good catch, thanks. Those number markings I wrote on the pipe are circumferences. The DPF/SCR interface is a 3" diameter pipe...

[TDIwyse]

Originally Posted by JDG

Awesome, thanks for doing this. Are you going to do a complete system whey you get a DP?

Planning to do little steps and measure/quantify changes...

[JDG]

Originally Posted by TDIwyse

Planning to do little steps and measure/quantify changes...

Id like to gut the whole thing myself and just add something to keep the noise down. I love turbo whistle, but ths car is my DD so I don't want it to crazy. Not even to concerned about performance at this point in the game, I just want the sound. Silly slow speed limits really take the joy away from copious amounts of torque.

Anyways keep up the good modding!

[BB_cuda]

Originally Posted by TDIwyse

Planning to do little steps and measure/quantify changes...

So, did you buy that whole long assy shown in the realOEM link? (EDIT: i studied the pictures and it appears the answer is Yes.) If yes, I'm curious if you are putting your original one on the shelf and modding the new one "in steps" as you stated? I may have some questions on measurements but i can measure my OEM one too.

Welding in your mods or using clamps? Probably a little of both i would think. Best of luck. The pioneer is yet again stepping out on the end of the tree limb .....

[BB_cuda]

One more for you please. Since you had the DEF injection tuned out as well, did you drain out the DEF and somehow purge the lines of that system? That urea stuff eventually crystallizes and would clog up. Someone who doesn't intend to use it again may not care but you seem the type to not butcher the OEM equipment (DPF aside ) and save it for a rainy day. Example was where you bought the Ebay EGR cooler to get the water fittings and left your OEM one alone. So, back to my original question. Did you/are you removing the whole SCR system tanks and all? If this were done, i could see how the stuff could be cleaned out with warm distilled water. Just sayin' ....

[TDIwyse]

Originally Posted by BB_cuda

So, did you buy that whole long assy shown in the realOEM link? (EDIT: i studied the pictures and it appears the answer is Yes.) If yes, I'm curious if you are putting your original one on the shelf and modding the new one "in steps" as you stated? I may have some questions on measurements but i can measure my OEM one too.

Welding in your mods or using clamps? Probably a little of both i would think. Best of luck. The pioneer is yet again stepping out on the end of the tree limb .....

Yup, bought the whole thing as shown.

I'm planning to alter the one already on the car and keep this new one pristine, in case I want to sell it to recover some of the $'s. Or if things get damaged/messed up with the modifications, I can revert to this new one. It's basically for risk mitigation.

Looking at things this morning I may start by cutting off the existing exhaust where the ends of this SCR part stop (so basically the muffler/tips) and using some clamped on angled bends (to direct the exhaust away from the underside of the car) to see what it sounds like "straight piped" but with the mid cat still in place. The end of the SCR section dual pipe diameters is just right for a 2.5" O.D. pipe adapter (had it lying around from my old jeep cummins conversion project) to slip on nice and tight, so making a quick clamp on angle adapter should be easy.

Then go to a "test pipe" in place of the mid cat and check sound and boost logs (to make sure "desired" and "actual" are in agreement without any overshoot) with the straight piped situation. But I'm thinking I'll eventually go with a resonator on each dual exhaust section where the mufflers are presently at, but I'd like to learn about the sound/boost impact along the way.

[TDIwyse]

Originally Posted by BB_cuda

One more for you please. Since you had the DEF injection tuned out as well, did you drain out the DEF and somehow purge the lines of that system? That urea stuff eventually crystallizes and would clog up. Someone who doesn't intend to use it again may not care but you seem the type to not butcher the OEM equipment (DPF aside ) and save it for a rainy day. Example was where you bought the Ebay EGR cooler to get the water fittings and left your OEM one alone. So, back to my original question. Did you/are you removing the whole SCR system tanks and all? If this were done, i could see how the stuff could be cleaned out with warm distilled water. Just sayin' ....

That's an excellent question, and I haven't addressed it yet. I was going to add some distilled water into the active/passive tanks and let that slosh around and then drain again. That should help the tanks, but won't help the lines. Unfortunately our winter season struck a couple months ago and it has sucked ,with horrible weather and extreme cold. All of which makes working on the car in the unheated garage suck. So, unfortunately, I haven't gotten around to doing a good job on cleaning the system.

Actually, I was contemplating removing the passive tank and keeping the active tank for my water/methanol system tank ... I think that would be kinda neat.

[JDG]

when all is said and done, Im thinking straight piped with one or two resonators. I want the turbo to have some sound but I don't want it so loud its all I hear in the cabin. I plan eventually to have a shop weld a single system straight back from the eco tune DP this will allow me to keep my complete exhaust system without damaging anything.

Well that's the plan anyways.

[JDG]

Originally Posted by TDIwyse

That's an excellent question, and I haven't addressed it yet. I was going to add some distilled water into the active/passive tanks and let that slosh around and then drain again. That should help the tanks, but won't help the lines. Unfortunately our winter season struck a couple months ago and it has sucked ,with horrible weather and extreme cold. All of which makes working on the car in the unheated garage suck. So, unfortunately, I haven't gotten around to doing a good job on cleaning the system.

Actually, I was contemplating removing the passive tank and keeping the active tank for my water/methanol system tank ... I think that would be kinda neat.

that's a very good idea actually. although why not just tap the passive tank since its larger? Or you could connect the two tanks to need a pump to fill the active tank.

Part of the reason I want to remove the tank is to be able to put a different bumper on there, without the fill door.

[TDIwyse]

Originally Posted by JDG

that's a very good idea actually. although why not just tap the passive tank since its larger? Or you could connect the two tanks to need a pump to fill the active tank.

Part of the reason I want to remove the tank is to be able to put a different bumper on there, without the fill door.

I was thinking the active tank based on how much fluid I use with my present setup and thinking that should be sufficiently large and would be less weight than the larger passive tank. But the passive tank might be easier to modify/use. Haven't started floor planning for this mod yet. I would like to move the H2O injection pump to the back of the car and lower to the ground for better weight distribution (it's in the engine bay now).

[FormerRotor]

Originally Posted by TDIwyse

I was thinking the active tank based on how much fluid I use with my present setup and thinking that should be sufficiently large and would be less weight than the larger passive tank. But the passive tank might be easier to modify/use. Haven't started floor planning for this mod yet. I would like to move the H2O injection pump to the back of the car and lower to the ground for better weight distribution (it's in the engine bay now).

I can't wait to see what you come up with here, TDI. I've been thinking the exact same thing about re-purposing the DEF tank. For now, I settled with this placement for the remote tank and pump. Makes for a clean install, but I hate adding weight behind & above the axel...
(This was obviously a shot of test fitment, final will be cleaner)


Honestly,I'm most anxious to hear how much weight you are able to drop with a less cluttered DPF-back exhaust design. Did you weigh all the stock components?

On a side note, I was able to house the tank and pump in the section above, but if you remove the tank & pumping assembly for the DEF, there is plenty of room for the pump below this compartment (still behind the axel, though)

[TDIwyse]

Originally Posted by FormerRotor

I can't wait to see what you come up with here, TDI. I've been thinking the exact same thing about re-purposing the DEF tank. For now, I settled with this placement for the remote tank and pump. Makes for a clean install, but I hate adding weight behind & above the axel...

That looks like a good fit. I've been using the existing washer fluid tank at this point, so no added weight from that. But moving the pump lower and farther back from where it's presently at would be a good thing. And freeing up the passive tank would open up some room and further reduce weight.

Originally Posted by FormerRotor

Honestly,I'm most anxious to hear how much weight you are able to drop with a less cluttered DPF-back exhaust design. Did you weigh all the stock components?

Haven't removed/weighed the muffler section yet. The car comes from the factory with the SCR section hard attached to the muffler section, unlike the purchased replacement SCR system. The realoem link shows you can buy a couple of the "CLAMPING BUSH" to connect the SCR back to the rear muffler after the pipes are cut. I'll need to cut the pipe on the exhaust to remove them, and don't yet have the clamps to reconnect if there are issues.

[BB_cuda]

Originally Posted by FormerRotor

I can't wait to see what you come up with here, TDI. I've been thinking the exact same thing about re-purposing the DEF tank. For now, I settled with this placement for the remote tank and pump. Makes for a clean install, but I hate adding weight behind & above the axel...
(This was obviously a shot of test fitment, final will be cleaner)
Attachment 966113

Honestly,I'm most anxious to hear how much weight you are able to drop with a less cluttered DPF-back exhaust design. Did you weigh all the stock components?

On a side note, I was able to house the tank and pump in the section above, but if you remove the tank & pumping assembly for the DEF, there is plenty of room for the pump below this compartment (still behind the axel, though)

That's odd to me, the picture that is. My left trunk panel doesn't have that sort of shape. There isn't a pocket like you have. The panel does have a plastic lid in the floor of it but it doesn't have that inboard wall like your's does. Same 2011 msport so i would have thought it would be same.

Also, notice your panel has the hole cut for the cargo "D" hook hardware to mount to chassis. Did your's come that way? I had to get an earlier year E90 panel from salvage yard to mount those cargo hooks. I cut the passenger side OEM one as I had a junk yard piece for a template.

[FormerRotor]

Originally Posted by TDIwyse

...The realoem link shows you can buy a couple of the "CLAMPING BUSH" to connect the SCR back to the rear muffler after the pipes are cut. I'll need to cut the pipe on the exhaust to remove them, and don't yet have the clamps to reconnect if there are issues.

That's good knowledge, and pretty interesting that BMW actually offers this. The company has always struck me as more of the "cut it and its your problem" type, but I'm certainly not going to argue.

Originally Posted by BB_cuda

That's odd to me, the picture that is. My left trunk panel doesn't have that sort of shape. There isn't a pocket like you have. The panel does have a plastic lid in the floor of it but it doesn't have that inboard wall like your's does. Same 2011 msport so i would have thought it would be same.

Also, notice your panel has the hole cut for the cargo "D" hook hardware to mount to chassis. Did your's come that way? I had to get an earlier year E90 panel from salvage yard to mount those cargo hooks. I cut the passenger side OEM one as I had a junk yard piece for a template.

I used to have the same one as that which you describe; I ordered up a Euro-spec liner with cd-changer option to give me a compartment into which I could fit the pump and 2.5g meth tank. I don't want to thread-jack, so feel free to shoot me a pm if you want some details.

[TDIwyse]

Originally Posted by FormerRotor

I used to have the same one as that which you describe; I ordered up a Euro-spec liner with cd-changer option to give me a compartment into which I could fit the pump and 2.5g meth tank. I don't want to thread-jack, so feel free to shoot me a pm if you want some details.

That sounds interesting. I'd like to learn more about it.

[FormerRotor]

Originally Posted by TDIwyse

That sounds interesting. I'd like to learn more about it.

Well, I knew about it because most folks stateside use it to house aftermarket amps in upgraded stereo systems and was able to ID the piece through realoem, but I found this thread when looking to give more detail here...
http://www.e90post.com/forums/showthread.php?t=419252

This gives all of the details on the full Euro "luggage compartment package". IMO, its probably how the car shouldve come in the first place with the exception of maybe the CD changer compartment. Enjoy.

[TDIwyse]

Just got this cut off. It's a lot heavier than I expected. Almost 40 lbs.

[TDIwyse]

Well, straight piping in place of the mufflers actually sounds really good (SCR mid cat is still in place, and the DOC portion inside the DPF canister is still in place). A little rumble on start up, a really faint hint of turbo whistle from the outside, and a nice sound inside the cabin when applying the skinny pedal hard. No drones or resonances that I could find in various driving speeds/rpm's. At cruising speeds it's not really different from how it sounded with the mufflers.

I had been checking out the youtube video's of 335d's straight piped with all the cats/silencers/DPF's out and I really didn't care for the very prominent turbo whistle, and I thought things sounded a little too "metalic" or "tinny". Think I'd get tired of that. But trying to base sounds from youtube/cell phone recordings and video's is not the same as hearing things in person.

I like how things sound with the present configuration, so I'm not going to fuss around with the resonators after all. The 2.5" Vibrant Ultra Quiet resonators weight about 6 lbs each on my scale, so they would be ~12 lbs + some pipe to bridge the distance, so probably ~16-17 lbs when its all done. Would still save about 22-23 lbs over OEM. But just having straight pipe (I've got 5 ft of 60mm stainless here) should only be ~6-7 lbs. So that would be a 33-34 lb savings.

I tried taking a recording of the sound, but it's too windy (9F air temp with 30mph NW winds) and most of what comes through is just wind noise.

[JDG]

Good work! I was thinking of dropping the mufflers and having cyba tips welded in but havent done that due to the up coming dpf delete. Want noise but not to much while cruising. Good to see you making progress