Break line bubble flair size

[Adams97Mark]

Hey does anyone know what size I should flair my 3/16" copper-nickle break line so that it matches what was existing (5mm) A guy at Toyota dealer had metric bubble flair tool which suggested 4.75 for 3/16 line then it jumps to 6 mm flair. The flair tool at auto zone has 4.75 then a 5mm which I assume was for use with original line but since I am using 3/16 line what will work with existing connection that is bubble flared to receive 5mm. Do I need to convert at proportion valve and rear caliper to accept 3/16 line or can I just use 5mm bubble flair tool on 3/16 line and have it fit like original 5mm line/5mm flare?

 

[Adams97Mark]

Ok, finally got both rear lines in using 3/16 line and flared with 3/16 flare kit. No issues of leakage at connections (used original 10mm/12mm nuts) which I suspected may occur due to size in brake lines not being same O.D I will say using the copper/nickle lines made the job easier in bending lines to route similar to the original lines, be sure and deburr the ends before bubble flaring to ensure a uniform fit to fittings. Also be sure and route lines so that you can reuse existing clips to hold lines in place in order to avoid any friction or movement of those lines. I didn't use lift to work under car so it was a difficult job to say the least, which after removing the starter on my back gave me the necessary edge.