OBM's sister site, Tiger Blog, has a terrific feature, 1984 Diary, commemorating the Tigers historic wire to wire championship. Brian wondered in one of his posts, whether any team had put together a better 40 game run than that year's Tiger team; which came out of the gate at 35-5.
Using Baseball-Reference, I did some research, culling through the game logs of some of the obvious candidates; the 1998 NY Yankees, 2001 Seattle Mariners, 2002 Oakland A's, 1986 NY Mets, and the 1916 SF Giants, owners of a 26 game unbeaten streak…. The best any of these teams could do was the 31-4 run the A's put together around their 20 game streak.
that out-streaked the Tigers was the 1906 Chicago Cubs (The Tinkers to Evers to Chance Cubs), who finished the season 116-36 (wow!). That year, the Cubs stood at 68-30 on August 4th, after a 7-4 loss to the NY Giants. From that point forward, the Cubs lost but 6 games the entire rest of the season, a 48-6 run that surely must be the finest extended run of baseball ever put together. That surge was highlighted by a 36-2 run, (12 game winning streak, a loss, 14 game winning streak, a loss, and a 10 game winning streak).
It should be noted that this was the first season for one of baseball's first true dynasty's, as the Cubs went on from '06 to post the best two season (223-81), three season (322-136), four season (426-185) and five season (530-235) win totals of all-time; an accomplishment unchallenged now for almost 100 years. That translates to a .692 winning percentage over a span of five years! Which happens to be one of the most amazing accomplishments by any team, in any sport, ever.