Cali 617 Test Pipe - PeachParts Mercedes-Benz Forum

mach4 · #1 07-22-2012, 09:17 PM

The OM617 engine in my 380SL has a California version of the engine rather than the federal. I've decided to build a test pipe to temporarily eliminate the trap-cat, also commonly called a trap-oxidizer as that was what was originally installed in the vehicle. The jig is being built with a junk yard trap-cat, so I will always have the original one available to reinstall once the testing is complete.

This wonderful technological device does seven things really well - it increases emissions, increases fuel usage, decreases power, reduces turbo performance, takes up a huge amount of space, forces the use of an expensive, special CA-only starter and reduces visible soot so the car appears to run cleaner.

To build a test pipe requires a stable jig that maintains the absolute relative position of the exhaust outlet and the turbo inlet, such that when the test pipe is installed in the vehicle it will fit properly.

The best solution is to cut the flanges off a clogged trap-cat and weld the new pipe to those.

Here is a picture of the trap-cat mounted in the newly fabricated jig.

To build this I fabricated a couple of plates that matched the turbo inlet and the exhaust outlet bolt pattern. I then bolted these firmly to the trap-cat and using sturdy angle iron welded up a simple yet sturdy jig to hold the trap-cat.

Once I had that done, I could cut the flanges off the trap-cat and prepare for fitting the connector pipe. My original intent was to cut the flanges with the trap-cat in the jig, but there just wasn't enough room to maneuver the cut off saw.

I'm not exactly sure what I'm going to use for pipe, but it will probably be just a 2" 180 degree piece of exhaust material that when cut, will provide me with the two 90 degree fittings I'll need and the straight pipe to join them.

The one tricky thing is the turbo inlet which is a rectangular shape so that will take a bit of fabrication and fitting.

More to follow...