Description: This 4mm spacer plate is designed specifically for use with WJ cylinder heads and crankshafts with a 110mm connecting rod. Are you using a cylinder head from another tuner with a squish band less than 2mm deep? Then we recommend a 5mm spacer plate for the correct compression ratio.
Note: When mounting on an original 180cc crankcase, the bottom two bolt holes must be drilled to 9 mm for a proper fit.