Still looking for a used '85 trap cat - PeachParts Mercedes-Benz Forum

Jeremy5848 · #1 06-10-2007, 01:03 PM

I'm still looking for an extra trap catalyst or trap oxidizer for the 1985 300D (W123) with the California version of the 617.952 engine. With a part in hand, I can visit the local muffler shops for bids on fabrication of a 'test pipe.' The purpose is to temporarily replace the trap cat for testing purposes. The pipe will also facilitate removal of the EGR valve as part of the test. (The pipe will not have the extra EGR outlet.)

I thought I had a line on one via my WTB notice in the 'Parts' section here but it faded out. Anyone have a spare trap or a parts car with one? I would prefer to borrow or rent but would buy if necessary. The trap needs to be dimensionally correct but I don't care if the innards are trashed. Anyone?

Jeremy

TheDon · #2 06-10-2007, 01:03 PM

I have some federal manifolds if you want to convert...

Jeremy5848 · #3 06-10-2007, 01:14 PM

Thanks for the offer. I have considered that but it takes a whole bunch of parts. I'd rather keep the car as stock as possible even if it does mean buying a $45 air filter every year or so.

lietuviai · #4 06-10-2007, 05:23 PM

I sold one about 2 months ago that had about 60K miles on it.

thatguy · #5 06-10-2007, 06:39 PM

Quote:

Originally Posted by Jeremy5848

Thanks for the offer. I have considered that but it takes a whole bunch of parts. I'd rather keep the car as stock as possible even if it does mean buying a $45 air filter every year or so.

That's my philosophy regarding the 85 Ca. straight pipe vs. converting to fed. I really don't think there is much more benefit to convert it vs. a straight pipe. Have you already taken your trap off or do you rely on the car as a daily? Perhaps you can measue it, I remember a while back someone posted a prototype of a bypass pipe, maybe if you take a picture of that with some measurements you can get a bid... Just a thought.

Jeremy5848 · #6 06-10-2007, 08:06 PM

Quote:

Originally Posted by thatguy

That's my philosophy regarding the 85 Ca. straight pipe vs. converting to fed. I really don't think there is much more benefit to convert it vs. a straight pipe. Have you already taken your trap off or do you rely on the car as a daily? Perhaps you can measue it, I remember a while back someone posted a prototype of a bypass pipe, maybe if you take a picture of that with some measurements you can get a bid... Just a thought.

Yeah, my trap is still on and the car is my daily driver. As to the bypass pipe prototype that was posted here, I may be able to borrow it. I also have a line on a spare trap. Negotiations, as they say, are in progress.

#7 06-10-2007, 08:44 PM

There are not many parts needed. Manifolds, down pipe and both oil tubes. You can still use the stock air filter setup.

bgkast · #8 06-10-2007, 10:06 PM

There was one on craigslist a few weeks back in portland.

linguica · #9 06-10-2007, 11:28 PM

Quote:

Originally Posted by Jeremy5848

Yeah, my trap is still on and the car is my daily driver. As to the bypass pipe prototype that was posted here, I may be able to borrow it. I also have a line on a spare trap. Negotiations, as they say, are in progress.

I mean...sometimes unfortunate things happen between long drill bits and Cats. Zero parts required, improved performance and mpg.

thatguy · #10 06-10-2007, 11:39 PM

Quote:

Originally Posted by linguica

I mean...sometimes unfortunate things happen between long drill bits and Cats. Zero parts required, improved performance and mpg.

I've thought about that too, but I'm very paranoid that something tiny will break off and get into the turbo and ruin it.

Jeremy5848 · #11 06-11-2007, 03:00 AM

Quote:

Originally Posted by linguica

I mean...sometimes unfortunate things happen between long drill bits and Cats. Zero parts required, improved performance and mpg.

That was discussed in an old thread I found while searching the forum last week. Turns out that an empty trap cat acts as a form of untuned expansion chamber that isn't good for the exhaust gas flow. Much better to replace it with a piece of pipe the same size as the exhaust manifold, so the argument went. Makes sense to me.

#12 06-11-2007, 03:07 AM

The stock setup has enough risk of chunking and damaging a turbo as-is. Running a drill through it would leave lots of loose bits hanging around and waiting for the least opportunistic time to kill the turbo for you.

linguica · #13 06-11-2007, 07:01 AM

Quote:

Originally Posted by Jeremy5848

That was discussed in an old thread I found while searching the forum last week. Turns out that an empty trap cat acts as a form of untuned expansion chamber that isn't good for the exhaust gas flow. Much better to replace it with a piece of pipe the same size as the exhaust manifold, so the argument went. Makes sense to me.

I would agree regarding the empty cat., but mine is not empty. Approx. a 2" hole straight through. I took great care to get all loose pieces out. Probably 2k miles ago....no problems.

vstech · #14 06-11-2007, 09:20 AM

Quote:

Originally Posted by ForcedInduction

There are not many parts needed. Manifolds, down pipe and both oil tubes. You can still use the stock air filter setup.

isn't the turbo different? If this is your only car, taking on the conversion back to federal is out. it may be worth it to get a second car, at least temporarily...if you have the space for it... obviously, I do...no CA cars though...sorry.

#15 06-11-2007, 11:59 AM

Quote:

Originally Posted by vstech

isn't the turbo different?

It's exactly the same turbo as the 84-85 federal model. All you have to do is reclock the turbine and compressor housings.