brake lines revisited

[Ishmael]

I've read a bunch of the threads and I think I've got a handle on the brake lines I need - I would like it if you guys could confirm for me though. I should be going 3/16 for all but the front to rear T which would be 1/4 for better adjustability afterwards. I should ditch the 4 wheel disc distribution block I have in favour of a prop valve.
Or could I go with 3/16 throughout and just use the distribution block? I know the line size has nothing to do with adjusting front to rear bias. The lines are going on my 68 firebird with c5 fronts and LT1 rears with power brakes and it will never see a autox.
What do you think guys?

[JRouche]

I put four wheel discs on my 62 nova. I run 3/16" for everything. I ran one line off one of the MC ports to the center of the firewall to a tee then ran one line off of that to each of the wheel cylinders. Then for the back I took a 3/16" line back from the other MC port to an adjustable proportioning valve just behind the front drivers seat. Then continued back to the rear end center and used a tee to split it, one line going to each rear cylinder. Stainless flex lines for each front wheel, one from the rear frame to the pumpkin and one each for the rear wheels. Right or wrong, I dont know, it works fine for me. JR

[Ishmael]

Do you find the brakes touchy at all? Do you think I could get away with the block or should I go to a valve?
thanks again

[Apogee]

As you said, line size doesn't significantly impact anything, so run what's easiest, cheapest, most readily available, etc for you. Larger diameter tubing does expand slightly more under pressure than smaller diameter tubing, so you could argue that the 3/16" should have less system compliance than the same system plumbed with 1/4" from front to back. Short of a well set up track car, most of us would be hard pressed to tell the difference at the pedal.

There are two general rules to follow when plumbing your brakes. First, run full pressure to the front brakes. Second, never run more than one proportioning valve in-line in any given circuit...lets just say the results are a bit sketchy and far from linear.

That said, you can remove the prop valve guts from your factory disc/disc combination valve and add an adjustable one or you can run it as is and hope that it's close to the proportioning your car needs. Most OE prop valve settings tend to be on the conservative side of things due to the number of vehicles they were used on and the various range of conditions (weather, vehicle loading, tires, etc) they were designed to handle, hence my preference to run adjustable prop valves over fixed ones.

Tobin
KORE3

[Ishmael]

Thanks guys, that eases some concerns. I'm going to plumb in ssbc adjustable prop block and pre-bent lines and be done with it.