Looking for a way to boost the performance of your 5.9|6.7 Cummins engine? Check out the Hamilton Cams 07-S-003 Valve Springs. These springs are designed for aftermarket camshafts and can accommodate over 50lbs of boost. With a 103# spring rating, they're sure to give your engine the extra power you're looking for.

Hamilton Cams suggests these springs if you are over 50lbs. of boost(or drive pressure) or over 3800 rpm or when running aftermarket camshafts. Hamilton has slightly lowered the pressure on this springs from 110# to 103#. If you are running over 4,500 rpm with a large cam, they suggest going with 103# springs with different processing for better longevity in extreme applications as well as their light-weight 4130 or titanium retainers. Retainers not included.