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.
vic
Thanks goes to DRTDEVL for the info.
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.
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.
Carry on.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
vic
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