So perhaps I didn't look hard enough in the newbie guide, but I couldn't find anything about which aftermarket systems were emissions approved in California. I really like the sound of the Alta system but don't know if it's Cali friendly. Any help would be excellent.

 

It is legal in Cali to change the cat-back part of the exhaust as long as it meets the states sound requirements. So, you are probably ok with most of the major brands unless it is a race exhaust or one that is on the very loud side. This is assuming you are using the stock exhaust manifold and cats...which I assume since you want to stay legal (no change of the stock exhaust manifold and cats are legal).

I bought the Alta exhaust for my '03 MCS, just haven't had time to install it yet.

 

Ok thanks, It will probably be the Alta or Borla exausts.

 

When I upgraded my '05 MCS, I was told that that the K&N Typhoon intake was, at that time (June '07), the only CARB approved custom intake(you get a lil' sticker with it to verify when you get it smog checked). Nobody else had spent the time & money to buck the politicians. At the same time I added a 15% pulley, a Millteck exhaust, Firebrand 8mm wires, Denso IK22 Iridium plugs, MSD coil. With an RMW tune I get 210 whp. I've had NO problems getting my smog cert. here in Seal Beach. The SCAQMD & CARB have no sense of humor.

 

I have found that during the registration required smog check, you usually can find a place that lets small things slide on the visual. Just need to make sure it can pass the computer/tailpipe emissions part.

 

Will changing the manifold affect the emissions too?

 

If you are referring to the exhaust manifold, sort of depends.

Anything other than the stock exhaust manifold and catalytic convertors (or a direct OEM replacement) is considered a violation in Cali. Having said that, you could run a different exhaust manifold with a catalytic convertor as long as you don't get reffed and it passes the emissions sniffer test.