Is the Z tube or pop charger that's rubbing the AC line?
 

i installed a Z tube, but i don't see it touching the AC line

I've heard people talking about this subject before but wasn't sure actually what they mean. I'm guessing they were talking about the metal spring clamp-screw rubbing the AC line but, if the clamp is put on reverse the screw is on the opposite side on the AC line and faces towards the oil dip stick (that's how my Z-tube is installed-no problems).

yea, i think my tube is not rubbing the ac line

Just look for any part of the tube that is touching the A/C line and rubbing. Some guys have reported a problem, others have said there's lots of room.
It depends on how the A/C line is run. If it's touching, you can carefully bend the A/C line out of the way.
C.

Definitely not the Z tube.

C-Keith is right when he says that the metal clamp could possibly touch the A/C line, and cause issues. The A/C line is made of very soft metal, which can be scratched or damaged easily. When I first installed my Ztube + JWT PC, I had some clearance, but a few weeks later I noticed some scratches on the A/C line (even though I had bent it out of the way). Even though you may have plenty of clearance, the Ztube does move while the car is moving, so it could potentially cause issues.

For preventative measures I went to Home Depot and bought some foam pipe insultation. I wrapped the whole A/C line in the foam insulation, and then taped it up with high heat rated electrical tape. If have be running with this solution for over 2 months now with no issues.

Here is how I avoided that same problem you had from happening.

http://www.mvtdesign.com/350z/ztube/1.jpg
http://www.mvtdesign.com/350z/ztube/2.jpg
http://www.mvtdesign.com/350z/ztube/3.jpg

Here is the screw crypten is referring to on the z-tube clamp at the filter housing end. You can rotate the clamp or reverse it just to make sure it isn't touching the AC line. As you can see there is lots of clearance on my G with the z-tube and the stock filter housing.
Wayne

it is the z tube that rubs on the A/C line. just wrap a little insilent around the A/C line thats what i did.