The Ring isn't in outer Mongolia!
Your car will be fine, so long as you keep an eye on stuff and have some mechanical sympathy. I trust you're not going to try and set any land speed records out there? My car was bog-stock first time out there and I didn't die, drive in accordance with your ability and the car's limits.
Tyres are a tough call mind, they'll be lethal in the wet on there especially under the trees. Maybe shift them on to someone as track tyres and get some PS2s/F1 asym.
Oh, I doubt you'll be insured for the Ring either - so bare in mind the 3rd party risks.
That's most important: be sensible and drive in accordance with your own ability !!
Nobody expects you to be faster than others. It's fun and no race. And having an
accident is least funny at all.
If in doubt improve brake ventilation - that's a serious issue in most cases. My brake
discs were blue after a few laps.
Don't go full throttle the last two kilometers. If you have to stop at Döttinger Höhe
with hot brakes some material of the brake pads will diffuse into the disc and cause
vibration.