i know they have different compression ratios but i was wondering if anyone knows if all of that is in the pistons, the rods, or if it's in the crank. or a combination. two of my pistons in my jdm vg30dett need to be replaced and i was wondering if i could just replace two of them with two j30 pistons or if possible i would have to change all six to the j30's. any help is greatly appreciated. thank you for your time.
