TUNE ?

I'd get a scanner hooked up to it and pull the codes. First find out what you're comptuer says is wrong. Exhaust mods like yours won't change your mixture raito.

In my opion anything that you do to the car that can bring in more air can cause some leaning. This has been proven over and over again on dynos. Just removing the MAF screen will cause a car to run a little lean.

Though, as modded, and w/o a blower any leaning that would result should be minor and not a problem.

For every dozen dyno tunes I have seen on a lightly modded car, I see maybe one that really needed a tune. I have only seen 5 - 8 hp gains in these situations. Not worth the money. Besides, how long will the tune hold? And, dynos do NOT replicate air flowing into the car as it is stationary on the dyno. Therefore, for such a slight tune, you might be doing more harm than good.

For example, I recently saw a video of an LM-1 A/F data logger being used on a car. On the dyno the car was lean, but on the street in actual conditions, it was slightly rich. Same car and same day.

I say no tune unless you have a compelling reason to get one such as fouled plugs, black smoke, etc... that can not be addressed in some other way.