From BruceBase:
The Sundance Blues Band made their commercial debut on April 30th 1971. The original line-up featured Southside Johnny (harp), Van Zandt (lead guitar and vocals), Lopez (drums and vocals), Tallent (bass) and Joe Hagstrom (rhythm guitar). Springsteen made several brief guest appearances during early May 1971, before Hagstrom left the band in the same month and was replaced shortly after by Springsteen. Bruce made his debut as a fully-fledged member on May 15th and would remain in the band until mid-July, when he departed to devote his energies to the newly formed Bruce Springsteen Band. The Sundance Blues Band would continue regardless, with David Sancious installed in place of Springsteen. The last known performance of the band was January 23rd 1972.
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From Castiles.net:
Steven and Johnny started a blues band with Garry Tallent and Bobby Williams and played regularly at the Upstage. They called it "Funky Dusty and the Soul Broom". They got the idea for the name from their theme song "Dust My Broom" by Elmore James. I think they were the first white guys on the Jersey shore to play songs by black Chicago blues artists like Muddy Waters and Little Walter. They later changed the name to The Big Bad Bobby Williams Band and later the Sundance Blues Band with Vini Lopez on drums. At the time the movie "Butch Cassidy and the Sundance Kid" was our favorite flick. Hence the name. Steve and Johnny always hung out together like Butch and Sundance.
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