Your smog experience will vary from place to place. I've been smogged with my turbo at a ghetto smog station around here. The guy didn't even care that my air filter was a piece of mesh clamped over my inlet. He also didn't seem to notice the blaring CEL that was ever-present at the time. You may be able to pass a smog check with a turbo setup, but the GReddy kits in stock form(no add-ons, period) are technically the only smog/CARB legal kits in Cali. I'm sure other states maye be a bit more lax on the whole emissions testing thing.