power vs. warranty
I put a cold air intake into my 08 v6 and it didnt void the warranty, but all the dealerships are different so you'll have to ask them
any exhaust work after the cats, will be fine. might not pick up much more than 10-15 hp though. spacing the throttle body is another way to help abit, but again not too much power to gain with that either. a cold air that wont require a re-flash of the ecu ( keep the factory intake, and use it when you need to bring the car back to a dealership....), or get creative with the intake and use the factory air box, but replace the intake tubing with a straight piping made out of something that wont hold much heat, and a few couplers to try and speed up the air flow ( might look funny, but cheaper than a cold air kit.. just keep in mind that you will need to cut a spot for the maf sensor, and for the breather tube)
Upload a new tune into the ecm with a handheld tuner. Reload the stock tune when you need to go back for warranty repairs. Also, replace your rear gears with some 3.90's or 4.10's. You can reprogram your speedo with your handheld tuner. Dont waste your time with an intake spacer. I'd throw in a centrifugal supercharger on it and take it off if i ran into issues. I'm a mechanic, so it wouldnt be to difficult for me to take it off, just time consuming.
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