These are our Sand Rail and Dune Buggy VW air cooled engine cylinder head spacers, these spacers are placed inside the cylinder head before final assembly, the spacers allow you to dial in your compression ratio and give you more CC's in your combustion chamber on your air cooled VW Sand Rail or Dune Buggy engine. by adding the spacers it will lower your compression to run on today's fuel
Regardless of whatever else I've had for cars I've always had at least one VW. Reliable and easy to work on. Chirco is without question the best place around Tucson to get quality VW parts and service.