When running higher rpm, higher boost and/or a more aggressive cam, valve springs need to be upgraded. our 12v springs feature 165# seat pressure, chromoly retainers and 10 degree locks. Our 24v Springs feature 103# seat pressure and chromoly retainers for use with the stock locks.
Hamilton 4BT Cummins Heavy Duty Valve Springs & Retainers
|Dimensions||6 × 6 × 6 in|