Engine/Transmission (1998.5 - 2002) Piston Grade

[drag racer]

Anybody know what the differences are between "Grade A", "Grade B", and "Grade C" pistons (as listed in the Dodge parts catalog)? It does not appear to be bore size, as oversized pistons are also listed. Something to do with compression height perhaps???

 

[john krmpotic]

The difference in piston grades is the height from the wristpin hole to the top of the piston. There is a . 002 of an inch difference between each grade. As far as I know this is the only difference.

 

[BILLVO]

Probably to compensate the compression due to a shaved head or block.

 

[Bob V]

If you look at a 12 valve service manual you will see how to get the correct ones. You could have all three grades on the same motor. Has to do with the piston height compared to the block deck height.