To get an accurate response, you should share what you have in mind for the car. Â*Do you want a fast street car or a car that will see a lot of track time?
If it's a street car and you want something fun to run around in and will be quick:
Lid, headers with a cutout, and 4.10 gears if it's an M6. Â*Do those simple mods and it'll feel like a totally different car.
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