There was a guy that passed a Hopped up LT1 camaro with a healthy cam in it by using a radio controlled stock electric EGR valve. When the smog dyno was running the 2500 RPM test (they do an idle, a 1500 load and a 2500 load test iirc) the guy hit the button and caused the EGR to manually open, (would not open stock at 2500 loaded) and his NOx emissions went down. It passed. Stupid CA smog. Those guys are so scared of passing something that is a little wild (even if it does meet the numbers) that they will stop the test and tell you to go somewhere else, or eyeball it and tell you they wont even test it. Their license (to steal) is always on the line and that is a good gig here in CA, captive audience and no shortage of tests to be done.
