The Edelbrock #9772 1.55" exhaust valve is a one-piece, swirl-polished stainless steel valve with a hardened tip and undercut stem for increased flow. Overall length is 4.930" and it’s sold individually. This valve is specified for Edelbrock #60797 cylinder heads to support improved exhaust gas evacuation.
Edelbrock 1- Chev E-Tec 170 Exh Valve 1 550 X 4 930