Originally Posted by nukefission
Yes, they are compatible. However, 1G pistons will lower your compression more than just "a touch." The ratio is 9:1 vs. 7.8:1. If you don't feel like pulling the motor, just pull the head and put the Mitsu metal headgasket in to lower the compression a bit. Set up a mild water injection system for good measure.
True, but if he goes that far he might as well change the pistons and ecu to have it running right without tuning out the ass.