Roller cams have aggressive Lobe Profiles. This requires higher spring pressure to keep the valvetrain under control.
The following table provides general guidelines for street/strip engines with a hydraulic roller camshaft.
| Engine Type | Seat Pressure | Open Pressure |
| Stock Small Block | 120 - 145 lbs. | 260 lbs. minimum |
| Moderate Performance Small Block | 300 - 360 lbs. | |
| High Performance Small Block | Up to 425 lbs. | |
| Stock Big Block | 130 - 165 lbs. | 280 lbs. minimum |
| Moderate Performance Big Block | 325 - 375 lbs. | |
| High Performance Big Block | Up to 450 lbs. |
Tips & Tricks
- Always use Screw-In Rocker Arm Studs with a hydraulic roller camshaft.
- The higher spring pressures will loosen press-in studs.
- Spring pressure over 360 lbs. require billet lifters.
- Stock, cast lifters will crack under high spring pressure at high rpm.
- Most manufacturers will recommend valve springs to go with each cam they make.
- We recommend using these springs, or a spring with similar specifications.