Out of the box- no.
SSD with SSDC can use variable speed pacers- but it is problematic. I don't know anyone who posts here regularly who has good success with it, but the SSDC users can give you a better answer.
Scorpius plans variable speed pace cars, but I don't believe they are available yet.
It is a more difficult task than it appears at first glance. You would almost have to have sector timing (part of the Scorpius solution, I think), as cars will not duplicate laps endlessly. Grip changes, braid contact is not 100% the same, and small inaccuracies can translate into big differences over time, etc.
Carrera users who feel they absolutley have to have a competitive ghost will often run a ghost car with magnets, and their own, driven car w/o. On a technical track, you can setup a ghost you can't beat.