Was there a post or article for DIY process to de-cat (piggie) downpipes ?
02-25-2008, 12:49 PM
#2
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There's a write-up in the Tech section.
Nothing too difficult. Cut cat at the seam, scramble the insides, re-weld it, and move the O2 bung. In fact, I'd be willing to bet that removing the downpipes will take more time than the mod itself :P
02-25-2008, 12:50 PM
#3
Holy sig!
Piggies are effectively downpipes with the precat mateirals removed and the O2 sensors relocated. Try searching the B5 S4 forum...tons of info on them, but keep in mind that it's illegal to do so for on-road vehicles...at least in the US.
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02-25-2008, 07:17 PM
#8
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yea only an idle test tho, in NJ they look for CEL's
and then do the idle sniffer test. my car passed just fine for emmisions and i have piggie pipes (with relocated O2 sensors so no CEL). im pretty sure no states do a load test due to the need for an AWD dyno, which most places dont have/want to buy...