Safely increasing cam lift or maximum engine RPM can require new valve springs. On the 3800 we use LS1 behive valve springs which means that when running new springs you will also need LS1 retainers.

• 90# springs are GM LS6 yellow springs*. The LS6 comes from the factory with .550" of lift and spins to 6500 RPM to give an idea of what the springs were made for. Seat pressure is lower than the Comp Cams springs but spring rate is higher so they do work well for aggressive ramp rates. There springs  work well with the VS, NIC, or XP cam. Because of the higher spring rate, timing chain dampener life is lower than with the 105's. 1.80 recommended install height.
• Comp Cams 105# springs are rated for up to .600 lift and work well with the VS, NIC, or XP cam. 1.80 recommended install height.
• Comp Cams 130# springs have the same spring rate as the 105's but the seat pressure is higher. Use of these springs requires a double roller timing chain. Rated for up to .600 lift they work well for 1.7 rockers w/ the XP, XPZ or custom setups with aggressive ramp rates or high RPM. 1.80 recommended install height.
• Comp Cams 150# springs have the highest spring rate, seat pressure and lift capability of all available springs for the 3800. Using them requires work on the head to cut a new spring seat. The install height is 1.90 and they support lift to .625

*Some users have reported that in naturally aspirated applications the LS6 springs have excessive noise and cause falst KR readings at certain rpm points. We have not confirmed this.

These are all packaged in sets of 12.