Is there a differince between these two blocks? I've heard they are the same, but c-speed's compression calculator says that they are different. It says th y8 has a deck height of .027, and the z6 and y7 are .000.
I am trying to build a y7 with pm7 pistons, a z6 head, and a z6 head gasket. I want this setup to be streetable and run on 93 octane, but the compression calc says this setup will be 13.6:1 . With a y8 block it should be like 12.5:1.
What should I do with what ive got to make this streetable?
I'd also like to know if the dohc zc rods will drop in to the y7, or will I have to get the pm7 pistons pressed on to the y7 rods? Thanks for the help.

 

the blocks are the same deck height wise, but the y8 has a .5mm p-to-d height and the y7 has a 0mm p-to-d height because they use different pistons.

for the most part, a d16 is a d16...if you put zc pistons in a y7, y8, z6 or a6 (using a 137mm rod) the p-to-d height would be 1mm. if the strokes, rod lengths and deck heights stay the same the piston changes what the p-to-d height is because the compression height of each piston is different.

btw...your setup would be about 12.03:1 static.