The Stovebolt Site Forums The Shop Area Driveline Break line / disc break upgrade questions:

I recently had delivered all the parts I ordered for my '57 break upgrade, and I have a few neophyte questions, if you'd be so kind:


1 - On the new master cylinder (5559MCA from CPP), there appears to be two ports for lines - a smaller one on the driver side of the unit, for the front left wheel, and a larger one on the rear of the unit for the other three tires. Oddly, what I'm assuming is the front tire port, is of a smaller diameter than the new pre bent SS break line I received, and the rear port is larger than the pre bent line. The front port seems to be sized for the smaller diameter back tire line (the ones that tee off to each tire). Should I use reducing adapters to get the new lines to attach - or am I looking at something totally wrong?

2 - I ordered a 10 lb check valve for the back tires (staying drum). I believe I should have ordered 2, and put one in between the wheel and the end of the line, is that correct placement?

3 - With the check valve (ordered from LMC truck) - came a spring and a small black rubber plunger. I'm not clear how those assemble in the valve, especially considering the black 'plunger' has a hole in the middle.

4 - The existing set up has a flexible hose from the T junction for the back to wheels for about 2' up to the hard line going towards the front. Is there a reason that flexible connection is there, and not a hard connection to the SS line?



Thanks in advance for your guidance -

Do not hook up just one wheel to the port. They belong in pairs. Both fronts to one port. Both rears to one port.🛠

"Both fronts to one port. Both rears to one port" - that makes WAY more sense, thank you.

What else did you buy for the installation? CPP installation illustrations show a combination valve. That's what I have. If you bought a combination valve, you have the residual pressure valve, proportioning valve, failure warning light contact all in one.

http://www.classicperform.com/Instructions/PDF/PVK.pdf

Thank you Gord - yes, I have the combo valve, and it was attached and plumbed up from the factory - but until you posted didn't assume they had a separate install instructions from the master cylinder. Thanks for posting - that clears some things up.

Did you run 9/16" to the back tee, and then split to 3/8" for each back wheel?

1/4" tubing to the back. It connects to a fitting where it changes to the rubber hose which runs to the tee on the rear axle.

9/16" - 18 refers to the threads in the combo valve. So, when you buy your 1/4" line it should have a fitting with 9/16" - 18 male threads to fit the combo valve.

All the CPP instructions (for all their products) can be found here: https://www.trifive.com/forums/showthread.php?t=34212

Wish they didn't call a combo valve a proportioning valve; it's much more than that. They also call an anti-roll bar a sway bar...

Perfect - Thanks again, Gord!