
D.S.S. MOD and PRO MOD COMPRESSION RATIO CHART
Common cylinder head combustion chamber volumes:
2 valve PI 44 cc ( OEM 1999 and newer)
2 valve NPI 51 cc (OEM 1992 to 1998 )
2 valve PI D.S.S. match port 44 cc (1999 and newer)
2 valve PI D.S.S. Full CNC Port 50cc (1999 and newer)
3 valve Ford Racing CNC ported 50 cc
4 valve Ford Racing CNC ported 52 cc
