Hi,

Avoiding the trap oxider is easy, just make sure you get a Federal version and avoid the CA MB cars. They all had the trap oxiders to my knowledge. I am not aware of Federals having this device, but I could be wrong.

Its very easy to spot on the turbo side and the way I recognize is that all the ones with traps have the big tube type filters rather than the 'chevy' round style as I like to refer to them.

You will want to avoid 82 and 83 unless you like 85 MPH speedos. They can be replaced but thats why I like the 84 and 85 vintage 123s.

Good luck,

Morph