You have no items in your shopping cart.
GSC Power-Division valve guides are made from a proprietary blend of Manganese Bronze and turned on dedicated precision CNC turning centers. With performance and aftermarket installation in mind we hold extremely tight tolerances on through hole concentricity to outside diameter which minimizes the required honing time for the installer. True to size outside diameters minimizes honing of guide bosses on cylinder heads that don't require boss service.