txcarbuilder

A friend has a '12 1500 Chevy truck with the 5.3 gas engine and he has asked me what I know about installing a chip or doing a tune to increase the HP for towing. I don't do that so I am doing some research. I find that there are quite a few devices available for this and was wondering if anyone had any experience with them and can give some recommendations on what will give him the results he is wanting. He doesn't have much to spend and would like to keep the price to under $500 so doesn't want to get into installing a lot of performance parts. Can he get much of an improvement without an aftermarket exhaust or intake parts? Any help will be much appreciated.