I failed smog again this year, 2 years ago i had the same problem. This time CA cars are tested on the dyno sniffer and they check for NOx now which means you have to have a good functioning EGR system. I know our EGR valves are negative backpressure valves and since i have a headers and a 3" exhaust i think it is hurting its functionality, my NOx output qualifies as a GROSS POLLUTOR but the car runs great. I get Code 32s on the freeway so i know there is something up. I know there are valves that dont use negative backpressure to open the valve, they just use ported vacuum. Can i use one of these valves instead and what valve can i use.

THANKS