Those #s put you somewhere around 275hp 'ish and 325-330ft lbs @ the crankshaft. Considering that your car is an auto, and the only things that you have done to the car that would actually give you (some) power increase are exhaust and a powertuner (chip), those look like pretty good #s to me.
As far as the A/F ratio is concerned, 14.7:1 is stoichiometric (ideal for burning all fuel / air entering the combustion chambers), so 14-15:1 is right where you need to be A/F ratio wise. Any higher and you will begin to loose power (and experience pre-ignition) due to a lean condition, and if you go much lower than that, you will likely be losing power due to it being too rich.
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