Actualy i failed my first try. Because my of my adjustable fuel pressure regulator and my crankcase ventalation wasnt going back into my intake system. Made a hoopty fix and passed. I made it easy on the rollers even with the H/C/I, definitly had tons of room. Probably just the 4 huge cats on the stock H that saved me a lot. So the Crane 2031 will pass CA Emissions rollers as long as you use the stock H, just thought i would let everyone know.