I looked these up on a site I found here, how do I know which one is correct for my vehicle? I know its a 5.7L engine and its a Vortec, but thats about it.
L31 Engine: 5.7 Liter V8, CPI
L31 ENGINE GAS, 8 CYL, 5.7L, CPI, 409CID, 400HP (SPECIAL HIGH PERFORMANCE-SOLID LIFTER CAM)