Actually, there's quite a bit that's CA legal, the tough thing is finding stuff for these trucks. A lot of the specific generation performance parts have been discontinued for years. Mine's a TBI, but same would apply to the Vortec. Currently, I have a Whipple supercharger, and I bring all the smog legal paperwork when I take it to a smog shop. I have a few other goodies that are CA legal. Of course, there are a few (very few) counties in CA that don't require the bi-annual smog checks. For example, Sonora county only requires when buying/selling a vehicle. I think there are a few others too, not sure how long that will last, though.