In 1958, Rudy's cousin, Al Pompilli, joined the Comets for a year, playing bass after the departure of Al Rex.
Rudy Pompilli co-wrote the hit "Week End" with Franny Beecher and Billy Williamson, which reached No. 35 on the Billboard pop chart when released as a single in 1958 as by The Kingsmen on East West Records, East West 115. He also co-wrote the B-side, "Better Believe It", with Johnny Grande and Ralph Jones. A follow-up single was released on East West, "Conga Rock", written by drummer Ralph Jones, backed with "The Catwalk", written by Franny Beecher and Billy Williamson, as East West 120. Pompelli composed the hit "Florida Twist" with Anthony Caruso, which reached No. 3 as an Orfeon 45 on the Mexican pop singles chart in 1962 based on the Billboard Hits of the World chart. "Florida Twist" has since become a party standard in Latin America and has been covered by many artists in rock and roll, Tex-Mex and other genres.