California emissions approved upgrades
 

Can someone point me in the right direction for stage 2 upgrades. I have (but not installed) the inner cooler. Looking to add more HP but need to stay compliant for smog tests etc. here in CA. Thank you for the help. 2011 R56 S stock. Downpipe options, CATs, Exhaust, Turbo upgrade, manic tune...

For downpipe options provided you stick with one with a CAT you should be fine. I've got a catless downpipe on mine with the Stage 2 Manic tune which puts the upstream O2 sensor in an unready state which will fail you so either stick with one with a CAT or be prepared to swap it out when you're due for smog. I spoke to Mario about this and the recommendation if you're running a tune is to switch it back to stock ahead of the test, you won't pass with an unready sensor. If you have a catless downpipe you'll be fighting some codes, you "should" be able to clear it just before you go in but YMMV.

CAT's: The only legal option are C.A.R.B approved models for Cali, though unless you're being sent to the state ref your average smog shop doesn't actually check them unless there's something obvious about your car being modded.

Exhausts: Anything after the CAT is good to change provided you stay under the DB limit. Again same with the CAT, unless there's something obvious about your car being modded you should be able to get away with a turbo back exhaust as OBD II cars really don't have much of a visual inspection anymore. Having a turbo blanket and aftermarket heat shield over the turbo will help with this as you really can't see anything on the exhaust side of the turbo without crawling under the car or using an inspection mirror.

Turbo Upgrades: You're restricted to either C.A.R.B approved ones, which I haven't seen for the mini, or you could swap in the JCW turbo as it did come on these cars. Your average inspector isn't going to match the serial number of the turbo to your VIN unless you give them reason to. The other alternative is aftermarket billet upgraded turbos using stock bored out housings. From outside they look like the factory turbo just with larger wheels and better flow.

Manic Tune: Provided you grab the switcher as well you can go with any of the tunes, you just kick it back to the stock tune before your inspection. Make sure you do it with enough driving time ahead to get all the sensors back in the ready state. ~30-50 miles should be more than adequate.

Same car, Same situation. I'll follow along as well because I've been thinking of all kinds of mods but at this point I'm sorta leaning toward it isn't worth doing that much unless you hit the track or something. Everything is such a hassle in CA unfortunately.

So far I have done the lower boost tube, the larger turbo inner cooler (finished today), and the torque mount insert. First drive tomorrow. Nothing I did threw any fault codes. I'll let you know what the differences are.