[DWR]

Originally Posted by BB_cuda

I want to keep the DOC intact. This is reason for switching from down pipe back to DPF. I will consider your method if DOC can be kept from being damaged. I like the idea of it looking unmodified. I do wish to cut off the differential pressure sensor tubes and seal off with welder.

I think it would be very difficult to do just the DPF. Not impossible, but difficult. it would take some redneck modifications of the removal tools.

I was really torn about the DOC. But when I saw part of it had been plugged by some soot producing experiments, I decided I was probably going to ruin the thing anyway. That is the advantage of the high flow cats, the matrix has larger openings. Unfortunately, that is also why they are not as effective at low temps, such as idling.

I think what surprises me is the smell of an uncorked 335d. I drove the old 300 series Mercedes diesels for years and really never minded the smell. The 335d is more acrid, sharp and unpleasant (or maybe I'm just turning into a sissy). The sound is a lot better though.

[Hoooper]

Originally Posted by DWR

I think what surprises me is the smell of an uncorked 335d. I drove the old 300 series Mercedes diesels for years and really never minded the smell. The 335d is more acrid, sharp and unpleasant (or maybe I'm just turning into a sissy). The sound is a lot better though.

Its the smell of a more complete diesel burn I guess. Theres definitely a big difference between computer controlled diesel exhaust smell and an old school 300D with mechanically controlled injection. Personally I think it smells fine but I do think its a lot more noticeable than the older ones.

[temporaptor]

Propel diesel HPR makes a big difference on smell for anyone who has access to it. After getting used to the sweet HPR smell, I had filled with regular diesel I was backing up fast and smoked myself out due to having the windows down. Wasn't a very pleasant smell. I avoid filling with regular D2 and only get enough to get me back to the HPR pump.

[TDIwyse]

Originally Posted by DWR

... But when I saw part of it had been plugged by some soot producing experiments, I decided I was probably going to ruin the thing anyway. ...

HA!

[TDIwyse]

Originally Posted by Hoooper

Its the smell of a more complete diesel burn I guess. Theres definitely a big difference between computer controlled diesel exhaust smell and an old school 300D with mechanically controlled injection. Personally I think it smells fine but I do think its a lot more noticeable than the older ones.

What I find interesting is the difference in smell between my 4 current diesel engines: CP3 335d, CP3 04 5.9L common rail Cummins without EGR or exhaust treatment from the factory, and 2 mechanical indirect injection diesel tractors with a Kubota and a Yanmar engines.

I think they all smell like victory, but using the exact same fuel the 335d has the least pleasant smell. It also has the lowest compression ratio of the bunch, which I think has something to do with it...

[dmanb2b]

Originally Posted by TDIwyse

What I find interesting is the difference in smell between my 4 current diesel engines: CP3 335d, CP3 04 5.9L common rail Cummins without EGR or exhaust treatment from the factory, and 2 mechanical indirect injection diesel tractors with a Kubota and a Yanmar engines.

I think they all smell like victory, but using the exact same fuel the 335d has the least pleasant smell. It also has the lowest compression ratio of the bunch, which I think has something to do with it...

Darn...this is making me think I should be considering a DOC on my DP....I could certainly have one welded in. Although the only time I would need it is pulling out of the garage/driveway from which I gather it does not help much anyhow, at low temps. Other than that I have a 30+ mile commute one way with 95% highway. I have UPS dropping off Iaknown's turbo back exhaust in my driveway today.

[BB_cuda]

Originally Posted by TDIwyse

I've thought about going back to this configuration as well, to get the DOC back into play.

Is there any possibility you could do some data logging on rpm/boost/EMP relationship for full fueling runs before and after? This is something I wish I would've done way back when, to be able to quantify the impact on back pressure for various stages in the delete process.

I've had the homework assignment for a while to get logging capability. I had gotten a zero on that assignment thus far. I will come back and think this over again. Keep in mind that my waste gate has been ported out to 9/16" diameter though.

Other reason I'm doing this is to see if it is quieter. It will be a weird combo of gutted DPF w/DOC and circuit werks exhaust without mufflers. It will still be loud is my prediction.

[BB_cuda]

Originally Posted by DWR

Small tip: if you can replace the engine mount screws with studs it will make it a little easier.

That and a "standardized" piece of pipe to hold up the engine, lol.

DWR, have you done this or only suggesting it?

After reading of yozh's experience with breaking off bolt into his exhaust manifold, my first reaction to your suggestion is the KISS principle. I would need to use the two nut method of putting studs in. Then, there would be the "do I use antiseaze or locktight question". \

Agreed, the line up thing would be simpler. I had the bracket off last summer (down pipe repairs) and found that if you started that one PITA screw with bracket pulled slightly away from engine (where you can see screw coming through the bracket wall) and then start the threads into the hole. It was fairly straight forward then. Getting the pig in place before putting bracket back, that will be some ***&&%%%!!! there.

Per TDI's earlier posting, I too want the less stink benefit with a real DOC, not a generic one. I had an idea at one point. Cummins had a DOC in the exhaust (between 2004 and 2007 I think). I was wondering how big it is and if it could be transplanted into a downpipe. I would really rather have the downpipe back in but with a DOC in it (not a generic CAT). TDI and I had been interested in a CAT that Mandrel bending solutions had on their website.
http://mandrelbendingsolutions.com/m...ded-converter/

It was stated to have a "heavy load" of precious metals to scrub more. Seems I recall he checked into it and they wouldn't sell it or didn't have it anymore. That shape factor seemed like it might work to be built into a downpipe at the near turbo end. Maybe its worth a follow up contact. For now, I'll fight the pig and get a cheaper less stink solution.

I will take my time with this as I need to get replacement sealing rings/parts for both ends of DPF, either buy more OEM bracket screws are consider DWR's idea.

I do have one more favor to ask TDI please? I need a dimension for cutting without cutting into the DOC. The picture will explain it best.

[BB_cuda]

Follow up on that heavy load CAT.

I called Mandrel Bending Solutions at 410-360-7105. Jesse says they have this part for sale. It is in 409 SS material. I was hoping for 304 SS. I mentioned a diesel application and she asked someone there. They don't recommend it for diesel. For $130, it might be worth a try. The ends can be trimmed to where you you can have a range of diameters to accommodate. Range is 2" to 3.5" so our 3" will work.

[TDIwyse]

Originally Posted by BB_cuda

...
I do have one more favor to ask TDI please? I need a dimension for cutting without cutting into the DOC. The picture will explain it best.

If my memory is correct, the post DOC EGT probe (2nd of the 3) is right in the gap between the DOC and the DPF. You could probably verify this by sticking a wire into the EGT hole and "feeling". I can go double check later to verify.

[TDIwyse]

This has a good discussion and some conversion vs temp plots different catalysts.

http://www.blackthorn.net/diesel-engines/

Another important characteristic of diesel engines is that the exhaust gas is cooler than that of spark-ignition engines, in some cases falling to a temperature of barely 100 C at idle.

Since catalytic reactions are temperature dependant, it is a good idea to find out the exhaust gas temperature for a particular application at an early stage.

Coatings on diesel catalytic converters can be varied to give ‘light-off’ at different temperatures, as illustrated on the following graph:

[BB_cuda]

Originally Posted by TDIwyse

If my memory is correct, the post DOC EGT probe (2nd of the 3) is right in the gap between the DOC and the DPF. You could probably verify this by sticking a wire into the EGT hole and "feeling". I can go double check later to verify.

Great idea and very simple to check. Thank you

[Yozh]

Originally Posted by TDIwyse

If my memory is correct, the post DOC EGT probe (2nd of the 3) is right in the gap between the DOC and the DPF. You could probably verify this by sticking a wire into the EGT hole and "feeling". I can go double check later to verify.

That, and if you look at the discolouration of the outer shell, you really can't miss it. There is a definite hue in colour of the metal where the transition from DOC to DPF is.

[Yozh]

Originally Posted by DWR

I was really torn about the DOC. But when I saw part of it had been plugged by some soot producing experiments, I decided I was probably going to ruin the thing anyway. That is the advantage of the high flow cats, the matrix is has larger openings. Unfortunately, that is also why they are not as effective at low temps, such as idling.

I have not done the "experiments" but am really curious how my DOC looks like after all this time. May be I can examine it from the back end so I do not have to remove that pig again. Do you have photos or more details on how plugged in it was?

[DWR]

Originally Posted by BB_cuda

I've had the homework assignment for a while to get logging capability. I had gotten a zero on that assignment thus far. I will come back and think this over again. Keep in mind that my waste gate has been ported out to 9/16" diameter though.

Other reason I'm doing this is to see if it is quieter. It will be a weird combo of gutted DPF w/DOC and circuit werks exhaust without mufflers. It will still be loud is my prediction.

If you need help with the data logging, I can get you up to speed quickly ... umm, assuming you can get a good bluetooth dongle or K+DCAN cable.

[DWR]

Originally Posted by TDIwyse

If my memory is correct, the post DOC EGT probe (2nd of the 3) is right in the gap between the DOC and the DPF. You could probably verify this by sticking a wire into the EGT hole and "feeling". I can go double check later to verify.

It is exactly as stated.

[DWR]

Originally Posted by Yozh

I have not done the "experiments" but am really curious how my DOC looks like after all this time. May be I can examine it from the back end so I do not have to remove that pig again. Do you have photos or more details on how plugged in it was?

Inspection from the back end might not work. The soot was in the front and filled the cells level with the matrix. I would say 15% of the matrix was closed by soot. Your results might differ.

I thought about pics after I had destroyed it.

[DWR]

Originally Posted by BB_cuda

DWR, have you done this or only suggesting it?

After reading of yozh's experience with breaking off bolt into his exhaust manifold, my first reaction to your suggestion is the KISS principle. I would need to use the two nut method of putting studs in. Then, there would be the "do I use antiseaze or locktight question".

Forgive my tone, too much time spent around racing engines will make you a fanatic about somethings ... First, studs are NOT supposed to be "tighted" down. Second, locking compound. Third, torque nut before compound dries/hardens. That is KISS. Superior clamping and way faster disassably to assembly. Nuts drive faster in a gun/air tool than bolts. Oops, sorry we aren't in the pits are we, lol.

[BB_cuda]

DWR, when I used KISS term, the last S was pointed at myself, not you. Hope there wasn't a misunderstanding.

I would want to thread lock the studs in so that when torquing the nuts, the studs wouldn't spin.

Appreciate the tips but I'm not using air tools. Last time I put the OEM Etorx bolts back in, I used antiseaze. It's likely overkill but every time I've had them out, I replaced with new ones. I bought 8 when I first put Ecotune pipe in and had the 2nd set for when I pulled DP back off. I'll buy 8 more. I have several other things I need to get from Husker anyway.

I'll let you know on the logging front as well. Thanks for offer

[Yozh]

Originally Posted by DWR

Inspection from the back end might not work. The soot was in the front and filled the cells level with the matrix. I would say 15% of the matrix was closed by soot. Your results might differ.

I thought about pics after I had destroyed it.

Interesting. Thanks for the reply. I'm very curious now how my DOC looks like. It is a fairly fine martix.

[DWR]

Originally Posted by BB_cuda

DWR, when I used KISS term, the last S was pointed at myself, not you. Hope there wasn't a misunderstanding.

If there was, it was my fault. We're good. Always will be. Cheers.

Originally Posted by BB_cuda

I'll let you know on the logging front as well. Thanks for offer

Your welcome.

[Trev88]

Just a random question is there a difference to the dpf deletes provided by supersprint vs ecotune for the n47?