Valve Springs in the small engine market, for example, 32-lb dual valve springs are 32-lb at approximately .930 install height but can also be 45-lb at .815 install height, depending on the spring's closed or seat pressure. Some camshafts may call for a specific spring seat pressure and rpm range. If you exceed the rpm range or increase the weight of the valve train, which includes valve springs, retainers, valves, rocker arms, push rods, and tappets, you may need to increase your spring pressure. Also, ensure you correctly have your rocker arms geometry, as it can impact valve acceleration and harmonics.
The cutter is designed to cut the floor of the head only. In some cases with hemi heads, the rocker stands/boss needs to be cleared to use the cutter. We do not recommend using the cutter to make this clearance.
Cutter Kit Specs:- 5.45 Pilot (5.5mm Valve Guide)
- .985" OD
- .600" ID
