cats
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From: Nebraska
99CLK320,
cats
question: Are the primary and secondary cats on ALL 208s basically the same. Reason I ask: could a person remove the secondaries and put them in the place of the primaries when they burn out and just live without 2ndaries? You proabably won't pass emissions testing in CA but what the heck, there's still 49 more states, eh.
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CLK W208
the seconadries are deffinatly are larger than the primaries so you might run into issues. as far as being the same the 430 and 55s share the cats and the 320s run a different (smaller) one. you might be able to delete the primaries and put the after cat O2 sensors after the seconadry cats.
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2002 CLK430
Ash het the nail on the head - you’d have to move the O2 sensors.
Way back when, we used to call the primaries "re-cats" Their job was to start cleaning up the emissions as soon as possible. Cats start working at about 550° F. Full efficiency doesn't take place until 750° F. Because the primaries are smaller, they heat up faster, and begin doing work sooner. If you only had secondaries and they were at operating temperature, you’d pass smog IF the O2 sensors were moved.
Way back when, we used to call the primaries "re-cats" Their job was to start cleaning up the emissions as soon as possible. Cats start working at about 550° F. Full efficiency doesn't take place until 750° F. Because the primaries are smaller, they heat up faster, and begin doing work sooner. If you only had secondaries and they were at operating temperature, you’d pass smog IF the O2 sensors were moved.
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02 clk 55, 13 GL 450
Dont confuse a working cat "reading" and the efficiency of the cat(s). The increased size or number of cats is to provide more material for more surface area. If you plan to dump 1 pair of cats, I'm not sure it will pass the sniffer test due to the lack of cataylist material? Of course location has everything to do with how involved that sniffer test is.
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99CLK320,
what prompted my original question was that I was hoping that I could delete my 2ndary cats and keep them for a future date when my primary cats need replacing. I live in Nebraska where we have no emmissions testing. The hope was to "perhaps" gain a bit by lessening exhaust restriction and have some spare parts for a future date.
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02 clk 55, 13 GL 450
I say wack those secondary cats out then... but like Ash said, they no gonna fit the tight spot the primary ones are in. Course when those go you could just go the kleemann route 
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CLK W208
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From: Nebraska
99CLK320,
ok, i get it. I've talked to Kleemann and their headers will not fit on the w208. they say they will but the Colorado Springs shop says there isn't enough room on the drivers side to make them work without putting a major dent in one of the down tubes to make them fit.
Last edited by dlbehrns; Jul 11, 2012 at 10:37 PM.
