BESTgasket is the world's premier manufacturer of gaskets for vintage and classic American cars and trucks. BEST Gasket valve cover gasket set for 1955-1957 Pontiac and GMC models using the 287ci (288ci), 316ci, or 347ci Pontiac-designed V-8 engine. P/N 20079E. BEST Gasket is the leading name in sealing performance in the restoration industry.