Engine Cylinder HeadThe Edelbrock #50169 Performer Cylinder Head is designed as a bolt on performance upgrade for 1987 2006 Jeep's with a 4. 0L inline six engine. They feature better flowing intake exhaust ports along with a modern combustion chamber design and back cut and swirl polished valves for improved flow. Retains the stock valve angle, pushrod length and valve cover bolt pattern for use with factory components and off the shelf accessories. Larger reinforced