Which version of the track? Which game? Which control method? They all make a difference of course. And are you after a qualy or race setup?
I have only used Roberto's track with magic I edited myself (I think he then added it to his track) but not sure I ever saved a setup. OTTOMH I would guess a rear wing around 15 is a decent place to start if you are just hotlapping, but I would be tempted to keep rear wing (and therefore top speed) at about the same as the CCs so agains as Erik says you should check the magic.
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