Maximizing Catalytic Converter Performance

[ferocity02]

I am running a single 4" diesel metallic cat with my front mount turbo system. The reason for this is purely to keep the fumes down since it's my daily driver. Due to space constraints the cat is about 6-7' after the turbo. Needless to say, I think the cat is not getting hot enough to be as effective as possible. However I'm not 100% sure that it's not operating correctly either. Would an NBO2 sensor after the cat indicate whether or not it's working properly?

What can be done in the tune to maximize the cat performance? The stock tune has various things like cat lightoff spark retard, AIR injection (don't have it anymore), etc that are geared towards getting the cats going. Can any of these things help me? I'm obviously only worried about cruising and idle. Running a little leaner should help too correct?

As for AIR injection, does it help? I can put it back on but it would only pump into the passenger side manifold since the drivers side is a log manifold.

Much of the piping is wrapped, but there is a ~3' unwrapped section right before the cat that I plan on wrapping to hold in the heat. Might also wrap the cat.

[joecar]

The closer the cat to the combustion chamber the better it runs (i.e. by avoiding loss of heat from exhaust gasses).

Also, cat runs the best when CL/LTFT trimming is working properly, but this relies on the cat getting sufficiently hot.

An after-cat NBO2 will show you what the cat is doing, if it is working correctly you will see specific behavior in the post-cat NBO2 waveform.

Do you have a pic of your exhaust system...

[ferocity02]

No pics of mine, but here is a picture of the kit mocked up. Mine is the exact same (except for a smaller downpipe). On mine the cat is about another 1.5' after the end of the downpipe.

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