Spark plug shims

[JWL]

The indexing "washers" replace the original plug gasket for the purpose of aligning the plug ground strap to the desired location. The variety of thickness options allows for differing thread calibrations so most rotational locations can be accommodated.

[Kray_Z-1]

Originally Posted by JWL

The indexing "washers" replace the original plug gasket for the purpose of aligning the plug ground strap to the desired location. The variety of thickness options allows for differing thread calibrations so most rotational locations can be accommodated.

Yes I understand the true purpose of the indexing washer. I did ask Speedway about the use of them, they say to use them WITH the gasket.