well you will need to get an aftermarket exhaust, air filter, a programmer (super chips, bully dog) and drive conservatively to get any worthwhile gains in MPG.
keep in mind, the stock system is the best CAI in my opinion. its just the stock paper filter element that needs changing. the tube is plenty large to get good air in, you just need a better aftermarket filter. using aluminum CAIs will just heat up the air inside and ruin any CAI benefits. just keep the stock piping and pop in a good aftermarket filter. amsoil and K and N are two good ones...
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