You have a stellar looking car, just need to make sure you get it into a different background, and bring your tripod and polarizer with you.
IMO the 85mm is the best portrait lens out there, all things considered.
- ease of use
- working distance
The 1.8 will be fine, but if you can snag a 1.2/1.4 you're even better off IMO.
The 85 isn't going to really compete with the 135/2, or 200/2, but again, all things considered it's the best.
For your car photography, you don't need a brilliant location, just something not-distracting. I took this on my drive the other day, just a quick snap.