Well I just had to buy a new Chevy and after selling my avalanche I had some money to play with I raised my truck 4" skyjacker and have 35's under it Have a K&N cold air intake and American thunder flow master cat back now do I need to have my computer flashed or buy a power chip or programmer so many and don't wan't to waste my money I think my spedometer is going to be off and I would like to see if I could get my mpg back after putting on these bigger tires. If any suggestions I appreciate it never got to up one of my trucks before mainly the mpg, and performance is the question at hand . or Have the truck DYNOed

 

Got any pics to post of it lifted? Also, will be interested in updated mpg numbers (gas won't stay this low for long).