170 pre-Syndication episodes or 156?
From The Lost Media Wiki
In a July 15, 1987 article in The Philadelphia Inquirer, Gail Shister says that from tomorrow to July 24, Harvey would be doing his Radio Show in his New York hotel room while taping 26 episodes of "Double Dare" there. But in an article from later that year on October 12, she says that there had been a total of 170 episodes taped up to this point.