Originally Posted by SHADY280

unfortunatly there wont be any legal headers for the L series motor, they are for "off road use only" besides that, your exhaust manifold will actually flow almost as good as a header, there are minimal gains on a low the medium modified z. there only really good if your raising the compression and making the whole engine flow more air. which of course are illegal as well.

Originally Posted by VernonZ

There is another option, you can extrude hone your stock manifold to make it flow better. That is what I did and then you can ceramic coat it.

http://www.extrudehone.com/auto/auto-afm.php

Originally Posted by MikeZ

San Diego is THE worst place for us to be. Straight up. Mods are not only watched dogged like crazy there. But there laws are so strict that cops are briefed on what to look for even if it is "stealthy", you could flat black everything in your engine and they would pop you for it... and if you are wondering muscle cars are slapped hard too. If you get caught racing they not only arrest you(like everywhere else) but they crush your car within 24hrs. With all you **** in it. And there's nothing you can do about it. Left your laptop in it? It will be crushed as well. SD is cracking down so hard, you can't get away with much.

Originally Posted by lww

I have Magnaflow's on all my Z cars. For me, they definitely have the best compromise between quiet while driving normal and angry rumble when you roll into it.