Changing Gears

How do you change gears when your playing in a tournament with a lot of players sitting out at your table and then they all get knocked out, or you just get switched to a new table without that many people sitting out.

I tend to play really well when im at a table with a lot of peopel sitting out and I'm just playing against 2 or 3 other people. In fact, many times, I will knock one of the people that are sitting in out, and then the tables will rearrange, and I will find myself playing a completely different game being against 8 other players sitting in.

I've learned from experience to tighten up a lot when I face this situation so that i can adjust to the new table, which of course is necessary when you go from playing 2 to 8, but it takes me a while to readjust. How long should it take to adjust? Any tricks?