Ok, I'm old enough to know that you use only steel brake lines with double flares. But I'm just prepairing a rear end for my project, and it has copper lines on it already and they are old and I don't remember why they should not be used. I need a refresher. Ice man
The burst pressure on the copper lines is a lot less than steel lines.You would probaly be ok if you have a dual resevoir master cylinder.If you panick stop the pressure in the lines might blow a fitting.I bought a 1940 chev coupe 30 years ago and the guy was running copper lines with a single resevoir and never had any troubles.I changed them to steel just to be safe.
Pure copper work hardens and becomes brittle, like when it's flared or bent! In a panic stop you can see 1200+ psi of brake pressure and there goes the old copper line.
Never use copper line for brakes as explained in the posts above. Brakes is the most important safety equipment a car has...never use any used brake lines...always replace with new steel lines.
just bought some new brake lines at napa, they are steel. they are black in color and are almost imposable to kink when you bend them. give them a try
The Jalopy Journal
