To avoid excessive and premature cam lobe wear it is important to use valve springs that provide the correct seat pressure. We recommend standard spring pressure, certainly no more unless you are consistently revving to 7000RPM.
Only just enough spring pressure is required to ensure the valve stays closed when it should be, without valve bounce. Any more is too much and will put unnecessary load on the cam, possibly resulting in premature cam lobe failure.

When choosing valve springs it is also important to check that the extra lift of our performance cams does not result in coil binding on full lift. This should be checked (even with standard cams) with the head and the valve gear assembled and valve clearance correctly set. It should be possible to leaver down the valve by an extra 3mm for safety.