What is the advantage of a steel shim over a copper one?
DuraShims from Innovative Machine & Supply are made from steel for several important reasons: 1) Steel has a higher heat tolerance than copper. In hotter running late model engines, heat resistance is very important to insure the integrity of the shim. Steel is superior to copper for this environment. 2) Steel cylinder head shims have a hardness factor similar to that of the block. This allows the gasket fire ring to properly “crush” as the head is torqued to spec. 3) Steel shims are less likely to be damaged in shipping and from mishaps in the shop.
