Well, I finally pulled the trigger and bought a set of Cayman S wheels (they are being shipped to my house as we speak). They are 8" fronts with offset of 57 and 9" rears with offset of 43. My stock 17" wheels are 7" fronts with 55 offset and 8.5" rears with 50 offset.
I know that the fronts will need spacers and I'm thinking somewhere in the range of 7mm-12mm. I will definitely need new lug bolts

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The rears could be left alone with an offset of 43 but I'm thinking of adding 3mm-5mm spacers just to give it that slightly more aggressive look. Will it truly be necessary to purchase longer lug bolts for this small of a spacer?
BTW, if anyone has spacers they want to sell, message me