Ok, I saw a D16y7 with a6 rods in it. And I was told it raises the compression of the motor. Well my question is, is the a set of stock d-series rods to put into a z6 to lower the compression?

 

The pistons are the big difference between D16 blocks. If you want to lower the CR of a Z6 use y7 pistons. The only reason I can see lowering CR is for a hi-boost turbo setup, though, and you'd be much better off using forged parts instead.

 

Trying to understand your post.

1. You saw a Y7 with A6 rods, cool.
2. They said it raised CR, probably not true since I think they are the same rods. The pistons would up the CR, not the rods.
3. Your actual question, which has NOTHING to do with your post, is that you want the lower the CR of the Z6, and you want to know what rods to use. Well, your stock ones will do, but Y7 pistons will lower the CR a good ammount.

If you lower the comp of a 9.5:1 (I beleive thats the Z6 CR), then you want high boost, then I suggest you want to go forged, as the rods and piston/piston rings tend to fail on high boost. Cheap aluminum...