I had the Banks Power Pak installed in a 97 Ford E350 with the V10 engine. Had it smogged numerous times (last time was 3 months ago), including one test a at a smog only station (they do a more complete inspection and was required by the DMV), I never had a single problem with the tech or the Calif. DMV, received a smog cert each time. So, my experience was all positive with the DMV.
BTW, the system performed as advertisted, except my mileage increase was very slight, if at all. I really liked the system
2006 Allure 430 #31437 (Cummins 400HP Engine), 2000 Tahoe Z71 Toad, Sanger V210 Ski Boat. Lifetime Good Sam Member, Lifetime NRA Member, US Army Vet