Test Pipes
 

I was wondering if I installed a test pipe on my mk3 and drove it regularly with it installed, then later put a new high-flow cat on then went in for emission testing in chicago area.. would I fail because they would be able to tell that I had previously had it installed?

it doesnt matter to them, what u had installed prior to the testing
as long as u got the cat, and other emissions goodies when u do the test
you will be good,
but if u have a heavy modded car,
b sure to go to a shop that can perform a pre-emissions test
that will probly cost about 50 buck
its better than those bastards at the emissions testing site telling you that you fail , and now go figure out how much can we get him to spend

cuz by this time u jus have to spend money to pass the test

hope this helps u
cuz im planning to do the same thing
run without a cat for two years, and jus put the cat again b4 the emissions test

yeah i plan on that to