Phosphor Bronze lifter bores

[ItBites]

CobraED,

It is much, much more common to use a screw-in oiling restrictor (they are much cheaper to achieve the same goal) to restrict top-end oiling.

Lifter bore sleeves are most commonly used to repair bores damaged during lifter failure. Second most common use is to produce correct valvetrain geometry as I described above.

If you look in the sleeve, you can determine the size of the cross-drilled oil hole. Easy way to tell if the sleeves were installed for restriction purposes.