How can i increase horsepower or overall performance on a 2011 gmc yukon?
Get a tune-up.
There is a bunch of stuff you can add on like a diablo reprogrammer, cold air intake unit, turbo or supercharging, catback exhaust system, if you want to go deeper you can change gear ratios, different cylinder heads, performance camshafts,pistons, nitrous injection, so it really depends on how deep your pockets are to how far you can go.
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