PAC valve springs

Well, we need to know what kind of cam you’re using. Hydraulic or Solid, Flat or Roller? Measure the OD and I.D. and the free length of the springs and post back, and we can probably tell you. Better yet, what does the Rimac spring tester say about installed height (seat) and open pressure? Also, what cam manufacturer or grinder? The 1.5 vs 1.6 ratio valve lift is more like 1.5 vs 1.52 lift ratio.