3" straight pipe exhaust - DRTDEVL

220629

Well-known member
DRTDEVL posted this in another thread. It was worthy of Write-up status but became a bit cluttered. Please post info specific to the mechanics of an exhaust system here.

Thanks goes to DRTDEVL for the info. :thumbup:

I had my exhaust guy build a custom, one-off exhaust yesterday... it took him several hours, and $500 later, I am a happy camper.

The original exhaust behind the OM647 was a 3" bell fitting on the down pipe that immediately necked down to 2.5", where it went to a flex pipe that reduced to 2.25"... and then through 2 cats, a muffler the size of a kitchen trash can, and then out the back.

Now it's a 3" bell, a 3" flex, and 3" straight pipe all the way through to a mandrel-bent 3" 45* angle tailpipe at the end. It is clamped together and has removable, color coded hangers in case I ever move somewhere that requires diesel emissions checks. He asked me to grab the down pipe off of my parts van to scavenge the bell fitting and hanger, along with making it easier to mock up a 3" replacement. The downpipe is made from stainless steel, while the rest is aluminized pipe. I'll probably give it a few days, and then clean it up and hit it with ceramic coating header paint all the way back in order to prevent any corrosion.

It kind of sounds like a deleted Cummins 6.7, only not nearly as loud. It will probably change a little more when I install the aluminum turbo resonator delete pipe and get the Green Diesel Engineering tune. My only worry thus far would be the placement of the O2 sensor bung... the sensor is about 1/8" farther out of the exhaust stream from stock. I am hoping this doesn't throw the van into confusion nor cause it to add too much fuel and kill the economy.

I'm tearing the van apart today for the 120,000 mile cooling service and the 60,000 transmission service, installing a 120a alternator, installing a power inverter, and several other smaller tasks, so it will be a couple weeks before I truly know how it runs and feels with the new exhaust. I only have Wednesdays totally off, and I don't think I will finish everything today, so it will be a week before its back on the road. I'll revisit this post with more driving impressions at that point, and again in a month when the GDE tune is added.
T1NddExhaust01.jpg

T1NddExhaust02.jpg

T1NddExhaust03.jpg

T1NddExhaust04.jpg

It's not loud at all... It makes just enough noise that you know something has been done, but it's still one of the quietest vehicles on my block.
Back on topic, I’d be interested to hear about any improvements in MPG or drive feel by doing this mod.
It will be a couple weeks before I can report this... I only have Wednesdays off. Yesterday I pulled the radiator and intercooler for replacement, and I replaced the idlers, tensioner, water pump, injection pump, alternator, belt, fan and clutch, all hoses and boost tubes, and washer reservoir. It's not fully assembled yet. Next Wednesday, I'm replacing the horn with a super loud dual horn set from an old rv, dropping in the radiator and intercooler, servicing the transmission, rotating the tires and painting the wheels silver while they are off, and installing a power inverter... along with a bunch of minor little things. I might not be done by that night, and will have to complete it the following week.
DRTDEVL,
The exhaust on my '01 has been modified.
To be honest I didn't pay much attention. The CAT is gone, there is a small muffler and the pipe exits the vehicle in front of the rear wheel on the passenger's side.
It was 'bus like' loud but not obnoxious. If the wind is right I get diesel exhaust in the passenger's side window if it is down and the van is stopped.

The engine runs fine and I was getting 24-27 mpg on local runs(van empty).

I'll try to get some better pics of the system when I get out of the snow(I'm headed for Florida from Wisconsin in a week or so.) I'm on crutches until March 18.

That might slow me up.



bill in tomahawk
Carry on.

:cheers: vic
 
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ClyneSnowtail

Active member
It was pretty good timing on this thread.
Discovered last week that the muffler was about to fall out of the sprinter, and so I ordered parts from summit racing on the company card. Found 2.5" pipe fits very nicely over the stock exhaust, so I ordered a 4 ft section of their 2.5" 16ga aluminized steel exhaust pipe, another section with a 45 degree mandrel bend, and a Walker "Commercial vehicle" 2.5" aluminized steel muffler. Part #22635 All of this was right at $100 delivered to the shop.
It took probably 10 minutes to cut all the old exhaust out, and maybe 2 hours to fab up the new exhaust. I cut the original hangers off the old exhaust and reused them to hang the new exhaust. I mocked it up and tacked it together, then pulled it back of to weld it all up. After reiinstalling it, I connected it to the original down pipe off the turbo and welded it up. Very simple and easy. Saved a bunch of time not going over the axle and just dumping it out the side. I did have to extend coming off the 45 degree with a piece of the original pipe. I shouldve ordered 2 of the 4ft sections of pipe, but it all worked out anyway.
Its a little throatier and if your standing out side and watching it go down the street, you can hear more turbo vacuum cleaner noise. It is not anywhere near obnoxious. Very happy with that muffler.
Overall a very budget friendly and Quick replacement for a rusted out stock system. We are coming into go season and wont get much down time and in fact I was barely able to spare the time I took to do it today.
https://www.youtube.com/watch?v=VCyBet42ujc
 
B

billintomahawk

Guest
I've been thinking about my exhaust system because it isn't stock and I don't know anything about it. I got banged up a couple of months ago with a broken hip so this is my first crawl under the Sprinter to snap a few pics of the system. Not sure what muffler I have and t looks like the CAT is gone. Looks like someone did a nice job.

Any help with identification is appreciated.













The sound is mellow, a little deep...in no way offensive...bus like.

bill in tomahawk who is darn excited to crawl under his Sprinter here in the Florida panhandle.


Here's a little music to sum the place up.

https://www.youtube.com/watch?v=w0BhwLamL_8

 
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220629

Well-known member
... Not sure what muffler I have and t looks like the CAT is gone. ...
I don't see anything that looks like a catalytic converter either. Not having it won't affect your engine operation. If it isn't required for annual emissions inspection then as applies to operating, you're ok without it.

Note:
For those who may not be aware. The catalytic converter is an important part of reducing toxic emissions and maintaining the emissions controls to proper specs. The converter should never be removed. If anyone feels further environmental warning is necessary please start another thread for that input.

:cheers: vic
 

DRTDEVL

Active member
OK, I can finally report back.

Yes, it spools faster and makes more power. t definitely helps with fuel economy. Unfortunately, when loaded heavy, it is just too much noise. I had the shop put in a 36" long 3" diameter resonator on Monday, as I was getting a headache driving long distance. Its still straight-through, it just adds a larger section with some glass matting inside to reduce the volume of the resonance that was reverberating through the van's body. Before the trip, I also had them put on a black 6" diameter tip, just to spice things up a bit.

On the plus side, however, I got exactly 20 mpg towing a 93 Chevy truck on an 18' PJ Car hauler to Wylie, TX, and 23.2 mpg pulling the empty car hauler back to La Cruces, NM.
 

ClyneSnowtail

Active member
OK, I can finally report back.

Yes, it spools faster and makes more power. t definitely helps with fuel economy. Unfortunately, when loaded heavy, it is just too much noise. I had the shop put in a 36" long 3" diameter resonator on Monday, as I was getting a headache driving long distance. Its still straight-through, it just adds a larger section with some glass matting inside to reduce the volume of the resonance that was reverberating through the van's body. Before the trip, I also had them put on a black 6" diameter tip, just to spice things up a bit.

On the plus side, however, I got exactly 20 mpg towing a 93 Chevy truck on an 18' PJ Car hauler to Wylie, TX, and 23.2 mpg pulling the empty car hauler back to La Cruces, NM.
Thats what I wondered about was the noise after driving for awhile, so I put the Walker muffler on. Its also straight through so I doubt its affecting anything. :thumbup:
Thats really good mileage. I assume probably going 60mph on your trip? I think I get like 20mpg too but I do 80 on the interstate and near 70 on highways even up the hills in the passing lane trying to get around the 18 wheelers.
 

220629

Well-known member
First. Thanks for the feedback.

... Unfortunately, when loaded heavy, it is just too much noise.
Remind me. Did you remove the OEM parts before the muffler too?
My 2004 with a rusted out nothin' of a muffler isn't loud, but the OEM parts before the muffler are still intact. The lack of a tailpipe might be a factor. A long(er) pipe out to the back may create a different situation for resonance.

... I had the shop put in a 36" long 3" diameter resonator on Monday, as I was getting a headache driving long distance. ...
How did you determine 36" long? Some calculation? Space available? Experience or recommendation of a muffler shop?

My plan was/is to go to a straight pipe, but I'd rather pay for a resonator up front if needed rather than adding one after the fact.

:cheers: vic
 

ClyneSnowtail

Active member
First. Thanks for the feedback.


Remind me. Did you remove the OEM parts before the muffler too?
My 2004 with a rusted out nothin' of a muffler isn't loud, but the OEM parts before the muffler are still intact. The lack of a tailpipe might be a factor. A long(er) pipe out to the back may create a different situation for resonance.


How did you determine 36" long? Some calculation? Space available? Experience or recommendation of a muffler shop?

My plan was/is to go to a straight pipe, but I'd rather pay for a resonator up front if needed rather than adding one after the fact.

:cheers: vic
Those 'other' exhaust parts will indeed make a difference in the noise level. Taking them off will make it louder. If you leave them on you could probably get away without a muffler or resonator.
 

DRTDEVL

Active member
Thats what I wondered about was the noise after driving for awhile, so I put the Walker muffler on. Its also straight through so I doubt its affecting anything. :thumbup:
Thats really good mileage. I assume probably going 60mph on your trip? I think I get like 20mpg too but I do 80 on the interstate and near 70 on highways even up the hills in the passing lane trying to get around the 18 wheelers.
65-70 the entire way.

I just got to Minnesota last night, pulling my overweight enclosed trailer. I got a scale ticket when I was an hour out due to curiosity, and I was around 15,000 GCW. No axles were overweight, but the transmission is likely unhappy with the combination. Overall? 17 mpg, with lots of headwind and crosswind.

First. Thanks for the feedback.


Remind me. Did you remove the OEM parts before the muffler too?
My 2004 with a rusted out nothin' of a muffler isn't loud, but the OEM parts before the muffler are still intact. The lack of a tailpipe might be a factor. A long(er) pipe out to the back may create a different situation for resonance.
Everything turbo-back s replaced. The original was a 3" bell to a 2.5" downpipe, to a 2.25" exhaust.

How did you determine 36" long? Some calculation? Space available? Experience or recommendation of a muffler shop?

My plan was/is to go to a straight pipe, but I'd rather pay for a resonator up front if needed rather than adding one after the fact.

:cheers: vic
The exhaust guy happened to have one laying around his storage room for a few years. It was available, and time to order things was not. It worked out great in the end.

Those 'other' exhaust parts will indeed make a difference in the noise level. Taking them off will make it louder. If you leave them on you could probably get away without a muffler or resonator.
The "other" parts? TWO Cats. (I was just looking at the stock exhaust last week as I tied it down to the front of my car hauler for the move)
 

220629

Well-known member
Everything turbo-back s replaced. The original was a 3" bell to a 2.5" downpipe, to a 2.25" exhaust.



The exhaust guy happened to have one laying around his storage room for a few years. It was available, and time to order things was not. It worked out great in the end.
Thanks for the feedback.

I think that the OEM system has one catalytic converter and a resonator right close to each other - when the parts were removed, my 2004 appeared to have 2 catalytic converters, but I'm not sure about that.

I'll leave my stock parts before the muffler intact. Based upon your experience, I'll likely look to source some sort of resonator rather than straight pipe. It will depend upon my mood and price of the part.

:cheers: vic
 
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220629

Well-known member
...

I'll leave my stock parts before the muffler intact. Based upon your experience, I'll likely look to source some sort of resonator rather than straight pipe. It will depend upon my mood and price of the part.

:cheers: vic
Based mostly upon DRTDEVL's experience/comments, I decided to go for a glasspack vs straight through exhaust.

For those who may wonder, I left the OEM catalytic converters completely intact. At 330,000, 338,000, Jan. 2022 343,000+ miles everything runs fine. I believe that the intact cats help with noise reduction for using a glasspak.

This is what I installed. The price I paid was lower than the Amazon listing.

Cherry Bomb 87516 Glasspack Muffler

Body: 26 inch
Overall length: 29.5 inch
Inlet: 2.5 inch
Outlet size: 2.5 inch
Body diameter: 3.5 inch

https://www.amazon.com/gp/product/B000EGL6C6
The end fittings are fairly heavy gauge that slip over a 2 1/2" pipe. They also fit over the catalytic converter perforated stub. Glasspack inlet/outlet = same size each end. Both were a bit loose fit on the pipes that I connected to.

The glasspack ends might even slip over a belled 2 1/2" pipe. I don't believe that a bell would slip over the glasspack end, but it might. I should have tested that. :bash:
I bought ss sleeve aka band clamp fittings for my installation. I found them superior for DIY to the traditional U bolt saddle clamps. They are easier for future disassembly too.

They come in various styles including reducing type.
https://www.amazon.com/Evilenergy-Joint-Stainless-Exhaust-Sleeve/dp/B076J5HSNJ

The 2 ea. cats assembled together with the glasspack made an approximately 48" L overall assembly. (Glasspack is listed as 29.5" overall.) The 2 cats + OEM muffler is slightly shorter overall if that info helps. The assembled glasspack + cats fit nicely into the 2004, but my exhaust system has been repaired many times and cobbled together so YMMV.

An aside.
I swear every time that I piece together repairs on an exhaust system that it will be my last, but my repairs are so inexpensive compared to system replacements that I just keep on doing it. Any pro shop would have $crapped out my 2004 catalytic converter$ and replaced with new cat$$$$.

I managed to get the cats loose from the muffler. It wasn't as easy as I hoped, but not too difficult.

How I prepped the Cats for the new muffler.

The cats are solidly attached to the muffler with sheet metal brackets. The catalytic converter metal is stainless steel. The 2004 parts still appeared as new. The muffler is aluminized steel. That wasn't at all new looking. The underside was at least 1/2 rotted away literally. The top sheet metal and bracket end was intact.

I cut the brackets loose using a portable bandsaw. Once the bracket cat side was cut free, I used a hammer to bang the brackets back against the muffler body to access the cat to muffler pipe connection. Fortunately when I knocked the brackets back the catalytic converter pipe backed out of the muffler slightly (reminder - my muffler was 1/2 rotted away so the muffler inlet connection was also weakened) . More banging while holding the cats revealed more pipe. Eventually I used a 2x4 and bar to lever the parts while hitting the muffler. A pipe stub turning into a perforated pipe was revealed. I exposed enough of that stub to allow cutting with the portable bandsaw. The glasspack slipped over that stub and wasn't a bad fit.

From there it was a matter of fitting the new glasspack, old cats and pipes into the old system.

I'm happy with the result. A freeway test drive was successful. The engine/exhaust noise seems no worse than the intact stock 2006 exhaust system.

:cheers: vic

Added:

Some pics of the glass pack and my extra sling supports. (A simple sling support may save the loss of your expensive to replace catalytic converter assembly.)


A Monel wire additional support for the cats. It is attached using a trucker bungee hook inserted into existing frame holes.

Braided ss picture hanging wire is an option.
https://www.homedepot.com/p/OOK-9-ft-100-lb-Stainless-Steel-Hanging-Wire-50116/100069689

ExhaustSupport01_resized.jpg

The glass pack with strap support. The cat pipe is inserted into the glass pack. I used muffler repair tape, ss tape with hose clamps to keep the seal.
The remnant of the one (of 2 ea.) cat assembly to muffler brackets that I cut off can be seen on the lower section of the cat. I love my portable power bandsaw. It made fairly easy work of removing those brackets.

My bandsaw is a Milwaukee brand. This is DIY worthy.
https://www.harborfreight.com/10-Amp-Deep-Cut-Variable-Speed-Band-Saw-Kit-63444.html

ExhaustSupport02_resized.jpg

ExhaustSupport03_resized.jpg

I didn't bother with any rubber isolators on my Monel wire sling. I haven't noticed any additional noise, but my truck has no additional sound insulation. It's just the basic Sprinter. It wouldn't take much to add some rubber donuts or other isolators.

Is there any benefit to the side pipe?
thx. m
For me the side exit exhaust was easier to source repair parts from the local auto parts house. It has worked fine on my 2004. So far I haven't noticed any down sides. I believe that it made my glass pack installation easier to fit to what was there.


Side Exit Exhaust
https://sprinter-source.com/forum/showthread.php?p=302931#post302931

vic
Added:

The pipe hanger stud can slip out of the rubber mount. I use a wrap of Monel baling wire for securing the assembly. A more elegant solution would be to drill a hole for a clip and washer.

VS30ExhaustHanger.jpg
 
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Perce

Active member
I too have fitted a 3” exhaust to my 2005 T1N 4x4 and have definitely notice an improvement in the low down torque and a smoother delivery of power. A worthwhile improvement for me??
 

220629

Well-known member
I too have fitted a 3” exhaust to my 2005 T1N 4x4 and have definitely notice an improvement in the low down torque and a smoother delivery of power. A worthwhile improvement for me����
Time will tell whether I notice a difference between my rusted out nothin' muffler and a complete 2 1/2" glasspack system with custom side exhaust outlet.

As to performance.
My premature expectation is that the 2 1/2" glasspack system will be no worse, maybe better than the perforated pipe stub out of the OEM catalytic converters. The holes in OEM muffler internal perforated pipe were fairly small. The cut off (for the glasspack) and now open ended perf pipe should have less restriction to flow. That was really the only restriction in the 2004 exhaust because the rest of the muffler was pretty much gone. Another flow restriction was/is the catalytic converters, but they are still intact with the new glasspack system.

With the pretty much gone muffler the 2004 did have better acceleration vs my 2006 with intact OEM exhaust system. I'll try to notice whether the 2004 lost its edge with the new glasspack revision.

:2cents: vic
 
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220629

Well-known member
Took a longer drive today. I'm very happy with the sound, or more accurately the lack of noise vs the blown out muffler.

...

As to performance.
My premature expectation is that the 2 1/2" glasspack system will be no worse, maybe better than the perforated pipe stub out of the OEM catalytic converters.
...
:2cents: vic
I would like to prove myself correct, but the performance is similar to what it was, not better though. If anything the turbo response may be a little bit less than it was with essentially no muffler. The performance is fine though. Initial acceleration is still a bit better than the 2006 with intact OEM exhaust system.

My guess is that if you are looking for a bit better performance the 3" system is worth considering. If you're just looking for a reasonably inexpensive aftermarket exhaust system, the 2 1/2" glasspack system as I installed will work just fine.

After inspecting the flex pipe I'm thinkin' my next repair may be replacing that part.

:2cents: vic
 

220629

Well-known member
If anyone cares...

A recent freeway trip confirms that the 2004 with 2 1/2" glasspack still has an edge over the 2006 with intact OEM muffler system when it comes to initial acceleration. I still mostly drive the 2004 so this is the first drive with the 2006 since the 2004 glasspack install.

Noise level difference 2004 vs 2006 isn't noticeable to my old ears.

:2cents: vic
 

220629

Well-known member
Bump.

I added some pictures of the glass pack and my additional exhaust system support to post #14.

:cheers: vic
 

alexk243

KulAdventure
Looking at doing this to my 2004 as my muffler and tailpipe have too many holes and I am loosing the patching battle...

Did you guys just add the glass pack? or that and a straight through muffler?

If I were to order an OEM tailpipe is that the 2.5" diameter? is it worth making the the jump to 3" if I am replacing everything anyways? Where is it 3", header? downpipe?
 

220629

Well-known member
Looking at doing this to my 2004 as my muffler and tailpipe have too many holes and I am loosing the patching battle...

...
I can't answer all of your questions.

I only have the glass pack that I indicated in my posts. No muffler at all.

The glass pack gives little back pressure compared to a full muffler. I used 2 1/2" pipe rather than worrying about staying with the OEM size.

:cheers: vic
 

alexk243

KulAdventure
I can't answer all of your questions.

I only have the glass pack that I indicated in my posts. No muffler at all.

The glass pack gives little back pressure compared to a full muffler. I used 2 1/2" pipe rather than worrying about staying with the OEM size.

:cheers: vic
Did you feel the glass pack was enough to quiet it down? Would like to have the least restriction as possible, but don't want to sacrifice sound level.

If I were to do the 3" pipe all the way back is the header come out at 3" and it gets smaller from there?
 

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