Start with the intake. Replace the Air box with a High Flow cone filter. Spectre 3" Intake for 25$ at O'Riellys. Next replace that muffler for an after market one. You probably will want a 40 series Magnaflow. 60$ to 110$ is a good starting price. Not too loud but sounds good. If money isn't a factor, go for a full exhaust. Those two will get you anywhere from 25 to 40hp. Just the intake will make it feel so much faster. Then maybe try a JET performance chip. Hope this helps you out.
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