Quote Originally Posted by ringle View Post
The last lap or two of a race sees very different circumstances for all teams and cars. Most cars are at this point are on their lightest fuel loads all day having only one or two extra laps of fuel in them. Combine this with many cars now driving in clean air, some cars turning down the revs (to preserve engines for the next race) as they have very little chance of improving or losing their position, some cars still racing each other for position, some cars engines on their second race and being able to explore the limits, and an varied assortment of other anomalies all leading to very different lap times.
If they are at their lightest, they can't be much lighter than just before pitting. Maybe it was track conditions?