Line sizing on disc conversions?

[newschool72]

I am in the process of trying to free up my rear brakes for burn outs at the drag strip. Before someone says "wrong site" (LOL) I am just trying to get my timing set by looking for best MPH at the strip. My question is.....should the brake line size be the same front to rear if running identical calipers on all four corners? My 72 Camaro came from the factory with front disc/rear drums and uses 3/16 line on the front brakes and 1/4 line to the rear split . I am going to install a prop valve in the rear line so I can back them off in the burnout box, and at the same time have adjustability for bias on the street and auto cross. My brakes have had a fairly soft pedal sense I put it all together and I am thinking it may be because of the 1/4" line running to the rears. Another issue is finding the fittings to go from 9/16-18 out of the back of the master to 1/4" inverted flare. I can find the 9/16-18 to 3/16 inverted, so if it will help the pedal feel by changing the line size AND I can find the fittings for the conversion( and I did) I will change out the line to the rear as well.
So question is....will I get better pedal feel with the same size lines all around on my 4 wheel disc set up? I am running 4 piston calipers w 13" rotors on all four corners.