That's a really good idea! you can also coil it too near areas where vibration is present to allow for relative movement.
Thats what i did with my battery cable. I found some red heater hose and slipped the wire into it then ran it through firewall and fenders to the trunk. It was a tight fit. I sprayed silicone based lube in there and pulled it through with a heavy string. It just provides an extra layer of insulation between hot wire and any metal surfaces.
I've ran copper for years without any problems, but.....I DO put a coil or loop near the engine to help with flexibility and vibration issues, and I DO run it through rubber anywhere it goes through steel like a firewall. I had a nylon one burn into on a header one time, luckily it sealed it off or I might have lost a motor. My current line is ran out of the AC drain hose hole in the floor pan, up the bellhousing and across the intake and down to the fitting.
I have run copper for years too, and without a problem - other than the restrictive slow actuation of the pressure gauges they supplied. I found that using 3/16 inch brake line cures the problem. the tube runs from the sender with a bulkhead fitting at the firewall and then to the gauge with another piece of 3/16 inch brake line.
I lost my first motor because of that, 75 on the freeway and started loosing power, the nylon line melted and sealed the pressure reading in the guage so it showed the engine still had a good oil pressure reading.. Finished driving to work figured my points took a crap or i lost time, got to work popped the hood and found oil all over the engine bay.. Had the car a whoppin 3 weeks when that happened....
I had a plastic line blow apart on me. Then ran copper for years, switched to braided when I installed Autometer guages.
ive ran copper for along time on many cars and have never had a problem, i go to my local farm store and buy it by the roll, i do run it through the fire wall with a rubber hose around it and i coil it, usually 3 turns. jeff
