Copper vs Aluminum for oil pressure line

I'm going to install a mechanical, backup Oil Pressure gauge in addition to the Dynon EMS - It needs a 1/8 in line to the manifold. Is copper or Aluminum preferred for this application? If one is preferred, why? I have copper, but can get Al if it is much better.

Thanks!

Copper is more ductile and seems to be the standard of the industry. If you use a firewall fitting, a couple of #3 aeroquip hoses would be even more reliable.

Let me start with the caveat that the mechanics on this forum will know better than I. With that said, I prefer copper in instances where the tubing is not moving due to vibration. I think in your example you are going from the instrument to the manifold on the firewall? I like copper because it's tougher and will hold the flare much better, particularly in a 1/8" tube. If it vibrates, copper will work harden over time and potentially fail. However, I've seen some old airplanes that have copper tubing under the cowl with little or no problem.

I used aluminum where possible

The only place I used copper was on the primer lines where I had to silver solder nipples to the end with a butane torch. I have a complete loop in every hard line between the engine an rigid terminations.

Bob Axsom