While I trust my service advisor at Hendrick to push for my unusual requests, they aren’t where I’d go if my car was more heavily modified. They’re OK with my K&N drop-ins but I remove my oil separator tank before I go in.
That being said, when I was shopping for my Stinger, Courage Kia in Gastonia was definitely into
mods. The salesdroid showed off the
mods on his Stinger, the service guy offered to install any
aftermarket parts I wanted and provided a few outlets for stuff he preferred (though he warned that many would affect the warranty…specific to the direct impact it might have), and one of the owners was previously of HUGE help to me with a rebuilt Mazda rotary engine when the company was jerking me around…and REALLY seemed to enjoy putting the moderately modified car through its paces while confirming my diagnosis of the issue, then personally supporting me against the company to get a good resolution.
I didn’t buy there only because they couldn’t acquire FROM A SISTER DEALERSHIP the perfect car for me. Note that I’ve never taken my car there, but when I start with decent performance
mods, I’ll go there first.