2003 GMC Envoy XL Valve Cover and Cylinder Heads

Using new head bolts when performing a cylinder head installation is always a good idea however, on late-model engines that came from the factory with TTY (torque-to yield) head bolts, replacement is an absolute necessity. TTY bolts are designed to exert the maximum clamping force for a tight head gasket seal, however they permanently stretched and could fail if re-used.

Fel-Pro gaskets offer 100% vehicle sealing with application-specific materials to give you sealing solutions with the performance and durability professionals trust.

These hardware assemblies were developed specifically for Holley Tall LS valve covers and are available as a single service component or a full set of 8. Each assembly features a polished Holley Tall LS valve cover bolt (M6 x 1.0 threads), an aluminum spacer, and an OE style LS valve cover grommet.

These hardware assemblies were developed specifically for Holley Tall LS valve covers and are available as a single service component or a full set of 8. Each assembly features a polished Holley Tall LS valve cover bolt (M6 x 1.0 threads), an aluminum spacer, and an OE style LS valve cover grommet.

Encore Automotive Valve Lifter is a steel cylinder designed to maintain zero valve clearance in a combustion engine.

ACDelco GM Original Equipment Engine Valve Lifters automatically help maintain a ‘zero’ valve lash condition to help prevent valve train noise and unnecessary valve train component wear, and are GM-recommended replacements for your vehicle’s original components. These original equipment valve lifters have been manufactured to fit your GM vehicle, providing the same performance, durability, and service life you expect from General Motors.

Sealed Power® parts provide innovative designs, use leading edge materials and utilize ISO & QS certified manufacturing in order to deliver top quality products that meet the rigorous demands of today’s modern engines.

This replacement valve cover matches the fit and function of the original equipment part that may be damaged or warped. Made from quality materials for excellent fit and superior heat resistance, this valve cover has undergone extensive testing.

These adapter plates feature an integrated oil fill and are pre-threaded for PCV ventilation fittings. Simply install the LS valve cover adapter plate onto your GM LS1, LS2, LS3, LS6, or LS7 engine to serve as your true valve cover, install the coil packs on top and route the wiring harness and spark plug wires into their designated locations, and use a perimeter bolt SBC valve cover of your choice to hide the unsightly coils without the need for any coil relocation and retention of all the benefits of OE style coil-on-plug mounting.

Whether you are a professional technician or a skilled do-it-yourselfer, you need easy access to Victor Reinz quality at every level of the engine all in one box and without any surprises. Protective packaging, informative labels, and state-of-the art electronic cataloging, ensure you receive precisely the gaskets and seals needed for a successful, long-lasting repair.

Fel-Pro gaskets are specifically designed for the repair environment to deliver a reliable seal on even the most troublesome applications. Designed for imperfect sealing surfaces and manufactured with proprietary materials, you can count on Fel-Pro for innovative sealing solutions for the real-world repair environment.

Four decades after its founding, COMP Cams keeps its focus on producing the highest-performing products possible, providing superior customer service and leading the industry in technological development. That commitment continues to resonate with racers, engine builders and enthusiasts worldwide, making COMP Cams the preferred choice for valve train components. COMP Cams is unrivaled thanks to its engineering staff – the largest and most highly trained in the performance aftermarket industry – sophisticated manufacturing processes, expert technicians and real-world testing on the track and street. The company’s integration of research, engineering and development, coupled with the free technical assistance it offers customers, makes it the Absolute Leader in Valve Train Technology.

Sealed Power® parts provide innovative designs, use leading edge materials and utilize ISO & QS certified manufacturing in order to deliver top quality products that meet the rigorous demands of today’s modern engines.

Fel-Pro® gaskets are specifically designed for the repair environment to deliver a reliable seal on even the most troublesome applications. Designed for imperfect sealing surfaces and manufactured with proprietary materials, you can count on Fel-Pro for innovative sealing solutions for the real-world repair environment.

Fel-Pro gaskets offer 100% vehicle sealing with application-specific materials to give you sealing solutions with the performance and durability professionals trust.

Fel-Pro gaskets offer 100% vehicle sealing with application-specific materials to give you sealing solutions with the performance and durability professionals trust.

Melling Performance valvetrain checking springs feature a low-tension design that allows them to be installed by hand for measuring piston-to-valve clearance, rocker arm ratio, and degreeing in a camshaft.

Sealed Power® parts provide innovative designs, use leading edge materials and utilize ISO & QS certified manufacturing in order to deliver top quality products that meet the rigorous demands of today’s modern engines.

“Competition Cams Flat 1 Piece Guide Plate Set Gm Ls With 5/16″” Pushrod And 8Mm Stud, 4854-8. ”

“Competition Cams Hi-Tech Rocker Stud for LS1,2,6 with 8mm Base Thread and 3/8″” Rocker Thread, 4554-1. ”