can anyone tell me what the stock cc's are for a set of 77' smog heads? when buying pistons the give a cc range for compression purposes and i'm wondering what mine are
The 77s used two different castings, both with 63 cc chambers. The 77 318 stock pistons have the largest top of piston to deck height of any used. The 67-69 pistons have the lowest and will bring compression to around 9.2:1. If you want more compression than this, you'll need to start milling and/or install aftermarket pistons.