Baseball-Reference Game Logs
In 2008, Boston is 76-55 overall. They are 58-39 in games started by Varitek.
In 2007, 96-66 overall, 73-48 with Varitek starting.
2006, 86-76 overall, 58-36 with 'Tek starting.
258-197 overall, .567 winning percentage
With 'Tek starting, 189-123, .606 winning percentage.
69-74 with non-Varitek starters catching, .483 winning percentage.
This does not isolate the '"pitch calling" effect he has though, as Varitek's bat is
significantly better than the guys catching when he doesn't - namely Mirabelli and Kevin Cash in the years in question.