brake lines question

[jlaird]

i'm gonna jump in here(don't want to hijack). Does anybody have any diagrams of the overall entire brake system for a 4 wheel disk brake setup. Because of various frame and crossmember mods, I think I'm going to build my brake system from scratch. I've been looking at inline tube and they have a universal street rod kit that looks feasible. Hopefully this question will be relevant to the thread.

[gringoloco]

Originally Posted by shifty

Do the 71-72 soft lines route across the front of the UCA also?

Do the 71-72 hard lines route like the 73-87 lines (with prop valve bolted up in front like that)?

No and no.

71-72, in my experience, use a shorter soft line that terminates at the mounting flange on the crossmember. They are basically at their limit when aired out- i.e. stretched.

The prop valves on 71-72 are still on the MC.

[shifty]

Hmm....

I really think the 73-87 setup looks like ass, though (where the valve is mounted).

I'm on the fence. It would take two minutes to weld soft-line mounting tabs on the '77 crossmember and just get a soft line 2" longer. I assume the caliper on the 71-72 and 73-87 has the soft line mount in the same general vicinity.

[AGRV8D]

this is a pretty damn good thread for us non edgjumicaded break folks

[SCOTI]

Originally Posted by shifty

Hmm....

I really think the 73-87 setup looks like ass, though (where the valve is mounted).

As opposed to the much better location hanging off the bottom of the master cylinder . . ....

[shifty]

I'd prefer it was mounted inside the frame rail, but .... mine is bolted to the MC with a 2" bracket, I don't think it necessarily looks bad, though.

If prop valves are that expensive, I recall seeing in the most recent TruckBuilder mag, something about aftermarket MCs that had integrated prop valves, I can't imagine they're more than $350. If so, I understand this means you'd need to make your own lines, but ... at the same time, $80 for a prop valve, $150 for a nice looking MC (chrome, polished aluminum or polished SS) you're talking another $100 to clean up the entire front-end....

[shifty]

Ok, let me tell you - Paul over at www.GMCpauls.com has been a friggin angle with trying to figure all this crap out, being really responsive to emails and actually broke out diagrams for the 67-70, 7-72 and 73-87 trucks and gave me a breakdown on what I'm looking at needing.

With that in mind, I'm going to head home and hang some parts and see what I decide. If I can find an internally proportioned MC like the one in TruckBuilder, I will probably buy it, weld tabs to the '77 crossmember, buy longer soft lines, and just forego all of the nonsense and headaches of routing everything across the front. I think the look will be a lot cleaner as well.

Although, admittedly, this approach may not be best suited to everyone. For me, my LS1 has all of my battery/alt/ground wires are routed through that front crossmember and loomed up, so mounting the mess of brake lines and prop valve to that crossmember will just look like ass.

Thanks for all the input so far. If anyone has additional ideas, I'm game!

[Shane]

you're making this more complicated than it needs to be. just use the stock 71-72 prop valve & lines everywhere but at the "soft" lines in the front ... weld the tabs and then use braided brake lines that you can purchase in whatever lengths you need as well as with whatever size end you might need. be aware that the right size brake line has a different size thread than the left side brake line.

edit: brake lines have different threads left to right ... not caliper.

[shifty]

I was wanting to nuke the prop valve altogether. I didn't see much more than $150 in savings buying an aftermarket MC with integrated prop, and it would simplify the lines.

Still somewhat mulling it over. I hafta weld up a trellis for our green beans this year, so I'll probably get to welding the tab this weekend while I'm doing that.

[Shane]

simplify the lines? custom made lines are VERY expensive and that's what it's gonna take with the aftermarket master cylinder / prop valve gizmo ...

anywhoo ... good luck

[shifty]

right, but it's two of the shortest lines to make, and i have all the flaring tools at home which will do 37/45 deg single/double flare. before i went braided for my fuel lines, i bent out my own aluminum lines. it was all single flare, and i hear double is tougher, but ... i dunno.

i'm probably going to end up going the way you're saying, Shane. your advice is exactly what Paul gave me @ GMCPauls that I was saying I agree w/earlier:

I found a book showing the routing of the 73 up brake lines and to go that route would be a mess as the lines go from Master Cylinder down and forward to frame where they enter the prop valve there, the front lines then exit the prop valve and go to either side of the frame where they then attach to frame and a rubber line then connects it to the caliper and the rear line exits the prop valve at drivers side frame and runs over to passenger side and down the frame to the rear.

To mate this to a 67-72 rear line set would be a mess.

Since the 73up crossmember is very similar to the 67-72 I would remove the welded on tabs on the 68 crossmember weld them to the 77 crossmember and buy either 71-72 lines & 71-72brake hoses ( if using 71-72 lines the tabs get welded to front of crossmember and I would use the lines to show the position they need welded on at) or use 68 Lines and weld to original rear position on crossmember and then use the disc brake conversion rubber brake lines to connect to the calipers.

I believe Inline Tubes price of $185.00 would be for a complete set of Stainless Steel brake lines (not just the front to rear line ) you can order through them or us. They do charge a 20% restocking fee if for some reason you change your mind and decide to go another route.

The lines do not include junction blocks & retainer clips.

This is how I've been thinking, just exploring other options and trying to get the questions answered that I think would get me there.

Thanks for the feedback. We may not think alike on everything, but ... there are some things

[Shane]

It's all about the trucks brudda-man ... everything else is conversation filler.

[Rreemo]

Originally Posted by Shane

you're making this more complicated than it needs to be. just use the stock 71-72 prop valve & lines everywhere but at the "soft" lines in the front ... weld the tabs and then use braided brake lines that you can purchase in whatever lengths you need as well as with whatever size end you might need. be aware that the right size brake line has a different size thread than the left side brake line.

edit: brake lines have different threads left to right ... not caliper.

I'm in a similar situation (doing a frame-up build) - 69' SWB Frame & crossmember with CPP dropped spindles on front that use 73+ brake components (using stock drums in back). So I've bought all new calipers brake hoses etc. from Napa, but still need to source the lines out now....this seems to be the best advice here - just order the complete SS hardline kit from LMC, I've already got a master cylinder, prop valve and booster from a 72'. I talked to a guy at CPP, and he told me to just use the 73'+ stock caliper hoses, but install them with a loop since they are a bit longer. Sounds like a half-a$$ bit of advice to me, so I think I'll return those and just go with the braided hoses up front.

Question that I have is about the fittings for the hard lines...to join them together (Y-block for front lines, barrel to connect to rear, etc.) - is there a place to buy those new as well, or will I have to piece that together from a parts store?

Nevertheless, good advice here - thanks!

[Brad]

Ok, Shifty I just did a search and found this post and I'm using the EXACT same model year parts and trying to make it all work. It sounds like Shane is on the right track and I got the same advice from Livrat, but when calling Inline Tube, the guy wanted to sell me a whole mess of parts that I don't think I need and it all began to add up very quickly. I'll be using the '77 combi valve that will mount near the MC and want to run the lines in the stock locations for the '68 and have it all work properly. It sounds like I just need 71-72 disk brake lines? I hate to ask since Shane seemed to verify above, but will someone else verify all this, especially with pictures?

I'm going to have to reread this thread a few more times to absorb it all and may call Wes up in Olympia to verify/order parts from.

[Brad]

I ordered '71-72 disc lines so we'll see what happens. 2 experts told me that's all I needed.