I am re-routing the brake lines out of the master cylinder to go UNDER the steering shaft instead of OVER it. The reason why i am doing this is because i need to gain some more clearance by the steering shaft

The smaller lines are 3/16" and i didn't have any problems buying some brake line from the local parts store and splicing them in with some tube nuts/sleeves and some -3an unions

My problem comes with the line that goes to the rear brakes. I assumed that it would be 1/4". But it might not be...i took off the fitting and cut the line to splice in some line and the fitting that screws into the proportioning valve wont fit over the 1/4" line for some reason

if i tap it on it will, but it doesn't fit

Anyone know if the line is some special size or something?

this is an 89 IROC-Z with 4 wheel disk brakes with the PBR rears

 

come on.....one of you have to know

 

It may be metric....if the ¼ inverted nut won't fit over the tube, then it's 7mm. If it was 6mm line, the nut would fit.
You may need to search out some standard-to-metric adapters and the right size double-flare tool for the metric line.

Pete

 

great......