put the stock exhaust on only to pass emission test then put it back on after.
you cant run 19psi on the stock downpipe with the cats in place its too restrictive and will cause the egts to go up and cause the car to knock.
you should be able to drive the car around with out a problem enough to get the emissions test but as for going into boost its probably going to start breaking up.
im pretty sure Jeff is going to say something similar
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