i wouldnt buy one of those e bay chips for anything!
i plan on using the trifecta tune also.
but if you want to go the chip route, use the jet chip. its a solid company, and a proven product..... thats my two cents.
How much HP does this the trifecta tune make on a stock cobalt, or does it require mods to work effectively. Just curious, as I heard some great things about it for the 2.2L. Also can you slap it on an automatic, or a manual only?