how to get more performance out of my 2005 tahoe
What kind of performance? If you want to make it go fast, you can't without putting a ridiculous crate engine in it, and if you want it to go around a corner you will need to learn how to cast spells. You can make it better off road, but at that point I would say just get a Wrangler and be done with it, because the Wrangler is lighter and smaller.
start with a after market air intake filter system and a low restriction muffler/s...then change the chip...
Older Chevys do good on super charger kits. Find an aftermarket kit for you size engine & add tube headers too.
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