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Hails from the land of rust!
Joined: Sat Oct 21st, 2017
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They're only there to operate during cold startup (cats work when they're hot, and it takes a few minutes for them to warm up)
The problem is that once they've done their "useful" stuff for the first couple of minutes, they're just restrictions in the exhaust system.
As far as engines are concerned, the worst place for cats is close to the engine, with the best place being right at the end of the tail pipe.
Because the cat reaction is heat based, the best place for cats, is closer to the engine.
Rally cars are run hard, so the exhaust gasses are hotter, their cats are in the end of the exhaust.
Regular cars have their cats just before the halfway point, this is a trade off for performance and emissions.
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2002 - 3.0 - 4x2 - Edge
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