Originally Posted by sherwood
the stroke difference isn't offset by the rod length. the static compression will be something like 12.3:1 because the longer stroke provides for a smaller piston-to-deck height.
The stroke is only 1.8 mm different between the LS and GSR cranks. The impact on compression would only be .2 compression points.
Since that is the case, JDM ITR pistons will yield a 11.3:1 static compression ratio with a GSR crank and 11.5:1 with an LS crank.