Anyone use CPP Master Cylinder & Booster w/stock disk brakes?

[DJ_Baar]

Put complete rebuilt '71 GMC 2500 (3/4 ton) disk brakes on my '67 Chevy C20 (3/4 ton) LB "Camper Special," to include rebuilding and replacing parts of steering, etc.... Got all new brake lines put in starting from back (already rebuilt Eaton H052 differential & brakes). (InLineTube parts I got for cab back worked fine.) But when I got to the front brake line kit provided by CPP (already installed new brake master cylinder and booster), and realized that their kit goes to outside of frame (not inside like stock on Driver's side) and different fitting sizes than that used on stock flex brake lines.... Anyone else deal with this?

Only threads I found was about leaks from CPP proportioning valve, (good to know though).

R/
DJ Baar

[TexasLS1]

Not sure if I'll be much help on this, but I'll at least help bump it to the top...

I replaced the master/booster/brake lines on my 72 - used Inline Tube and master/booster very similar to the CPP. Fitment turned out great but I did have to do some light massaging of the lines and re tightening of fittings to get everything lined up and not leaking. I can't remember the exact differences between steel line routing but I do know that the hard line routing is different between the earlier models and later models (iirc routing in front of the crossmember for 67-70, and behind crossmember for 71-72??). The lines that drop down from the Prop Valve run outside the frame on mine. The rubber brake hoses are specific to the side they go on, so you might try switching Passenger to Driver? I think I had mine on the wrong side when i went to thread in the fittings and swapped them.

Hope this helps a little, keep us updated...

[DJ_Baar]

I thought attached adapter would take from CPP lines to stock front disk brake flex lines. And coupler required to connect rear brake lines, stock size at line. (Rear lines are 1/4" with 7/16-24 flare fittings.)

But ran into another weird thing. Went to put front lines on again and found that only left (driver) flex line needed adapter. I assumed when I found the left new brake line matching old drum brake fittings, right (passenger) would be same, but no.

I knew front disk lines were smaller than rear. But now why is one side one size fitting and other side different size, (unless I got something wrong)? Flex hoses look correct and made sure had tang for caliper connection correct for each side. But new front lines have 7/16" 24 TPI inverted flare driver side and 3/8" 24 TPI inverted flare. So is this normal? I doubt it but do have adapter to make it work now on driver side.

WoW --- getting the correct parts from Parts Suppliers is even a challenge, (too many examples of what I knew was wrong and had to argue).


R/
Dave

[DJ_Baar]

TexasLS1,

My '67 has hardlines behind crossmember. Pictures were provided by CPP Rep to help. Only difference is I need to route now to outside of frame and modify inner fender.


R/
Dave

[DJ_Baar]

Answered my own question, Rock Auto sent me one incorrect flex brake lines and too late now to return (long running project). Got Friend from AutoZone working it. Hell even the frame point to attach flex to hardline needs to be modified for the drum to disk brake conversion 12 point for hex is too small (a little filing will fix that. But it would have helped if I got the correct flex lines I ordered - looks same except one is 7/16 vice 3/8 and that size effects both ends & I didn't catch that until today.

R/
Dave

[TheRocket]

I have a 1971 C10 Custom. It is far from original. It came with a 250 inline 6 and three-on-the-tree. Manual steering, manual brakes. Front disc brakes, rear drum. Many years ago, I replaced the manual steering with power when the steering box wore out. Later, I replaced the brake booster/master cylinder. That company is no longer in business. Maybe 5 years ago I had to replace that so I purchased from CPP. I have had no problems with it.

Today, I am running a local built 350 with a 700R4 transmission. On top of the motor is the fuel injection from my son's '89 Firebird. I purchased a transmission crossmember from CPP and it fit fine, except a slight modification on a couple of the holes. I am very happy with my purchases from CPP.

To disclose, I am not a mechanic. A local mechanic replaced the steering box and original brake booster set-up. He replaced that with the CPP. He replaced the 6 cylinder with a 350 and a 3-speed automatic. My sons installed the new motor/tranny/fuel injection which was made easier by the prior conversion.

We are rewiring with a Painless Performance chassis harness kit. We are very impressed with it.

I would purchase from CPP again.

[DJ_Baar]

So far OK with CPP. Did my research before and they helped with pictures I provided too. But so far three other reputable companies had items "miss-packaged" (like wrong item in opened box or plastic bag). Mistakes happen and takes time to correct, but another setback.

[DJ_Baar]

My error, found the original receipt for FRONT BRAKE HOSE SET, and it was purchased from LMC Truck. Not first problem with their parts since buying this truck only just last July. Was NOT Rock Auto purchase and only problem with them is just not having all parts needed. My humble apologies for getting that wrong.

R/
DJ Baar

[TexasLS1]

Glad to hear you're getting it figured out. Love your pics, the progress looks awesome so far! Really liking the black and blue.

[DJ_Baar]

I confirmed that the Driver’s side does have a larger diameter fitting and will require the use of 1 inverted flare adapter (7/16" to 3/8"). And more importantly the ¾ ton trucks hoses are the same size but one inch longer than the ½ ton.

I did use front hard lines as part of a conversion kit I bought from CPP along with master cylinder and booster. And both ends for front brake hoses are 3/8" flare fittings.

I have now purchased from two different sources trying to get correct replacement. One had two part numbers, one for 1/2 ton and different part number for 3/4 ton, but a bit long and fitting to go in frame bracket was odd 17mm requiring modification of bracket or hose fitting. Other were slightly too short (with wheel turning and suspension movement. Also had two size flare fittings BUT had 5/8 inch fitting for one side but other was larger 17mm again for other side. See pictures of examples with steel rule for length.

Simple project turned into a real headache trying to get this last part(s). Complete rebuild of front and rear brakes, all lines in between, steering and suspension, and Eaton H052 differential. All but still need correct front brake hoses to complete this. Contacted a couple other sources and awaiting feedback on particulars this time before ordering.

DJ