Since this seems to be a recurring topic in the LFX section by folks new to the 2012+ 3.6L LFX engine, I figured we should compile a single thread and hopefully get it stickied so it's easier to find and reference.
With the release of the 3.6L v6 named "LFX" in the 2012 Camaro LS and LT models, General Motors released an engine with a radical new head design:
the exhaust manifold is integrated into the heads. This means that you cannot "install" headers on an LFX engine. Additionally, the 2012+ LFX engine uses a composite intake manifold instead of the metal previously used.
While the knee jerk reaction is "I WANT HEADERS!" - as a new owner to a vehicle with an LFX engine, you'll soon realize the advantages outweigh the negatives. For starters, the LFX engine is 20 pounds lighter than the previous 3.6L LLT engine used in the 2010 and 2011 Camaro LS and LT models. The composite intake manifold combined with the integrated exhaust manifold allowed GM to shed weight from the engine. The composite intake manifold helps to reduce heat soak, so while guys with LLT engines need to add spacers to isolate their intake manifold from the engine block to minimize heat soak, we (LFX owners) do not have to! Additionally, the LFX engine makes 11 horsepower more than the LLT. One other thing to mention would be that the MAF was changed from LLT to LFX so you cannot use a cold air intake designed for a 2010-2011 Camaro unless the manufacturer specifically states it will work on a 2012+ Camaro.
While it may be unfortunate that we can't get the exhaust tone that normally comes with a set of headers, consider it a savings to your wallet - focus your attention to the true bottle necks on the LFX engine -- the catalytic converter and muffler. Buy a nice set of high flow cats and a new exhaust (axle back or cat back) and you're done with the exhaust.
For more information on the LFX engine, check out the communication from GM:
http://media.gm.com/media/us/en/chev...ro_engine.html
