i think it was episode 36 with johnny fish and the fins at the concert they did a song called youngblood the real group is called flash cadillac http://www.flashcadillac.com/FlashCadillac-Youngblood.mp3 it's the bands website so i guess it's not piracy

I saw Flash Cadillac live. It was years later and they were opening for a Beach Boys reunion tour. Unfortunately I didn't know who they were until sometime afterwards.

The Beatles recorded a version of "Youngblood" I believe, in the early 60's. It was on a 90's reissue of their Hamburg live recordings.