Piper Cams single valve springs with combined stem seal retainers for the Z20 LEx engine.
Uprated valve springs are a worthwhile investment for any Z20 engine intended for vigorous use, especially with regards to high revs / high load.
During the process of fitting springs, the stem seals are also accesible so it would be rude not throw a new set on.
This kit includes the combined stem seal retainer which allows you to kill two birds with one stone, replacing old worn stem seals and adding the support of the retainer body to help prevent failure.