Operation CHARM: Car repair manuals for everyone.

Piston and Bore Dimensions

Standard Sizes
Tolerance Group 0
Piston Size 99.98 ± 0.007 mm (3.936 in ± 0.0003 in)
Bore Size 100 ± 0.005 mm (3.937 ± 0.0002 in)
Tolerance Group 1
Piston Size 99.99 ± 0.007 mm (3.9366 ± 0.0003 in)
Bore Size 100.01 ± 0.005 mm (3.9374 ± 0.0002 in)
Tolerance Group 2
Piston Size 100 ± 0.007 mm (3.937 ± 0.0003 in)
Bore Size 100.02 ± 0.005 mm (3.9378 ± 0.0002 in)

1st Oversize
Tolerance Group 10
Piston Size 100.48 ± 0.007 mm (3.9559 ± 0.0003 in)
Bore Size 100.50 ± 0.005 mm (3.9567 ± 0.0002 in)
Tolerance Group 11
Piston Size 100.49 ± 0.007 mm (3.9563 ± 0.0003 in)
Bore Size 100.51 ± 0.005 mm (3.9571 ± 0.0002 in)
Tolerance Group 12
Piston Size 100.50 ± 0.007 mm (3.9567 ± 0.0003 in)
Bore Size 100.52 ± 0.005 mm (3.9575 ± 0.0002 in)