Hi,
Contemplating converting the front drums to disc on my ‘70 Supreme. As many forum posts reference Right Stuff and In-Line, I found a possible kit from In-Line but had a question about the lines.

Currently I have 4-wheel manual drum brakes. By converting to the front disc, the kit comes with the disc/drum MC and a booster with proportioning valve. As my current setup only has the distribution block mounted to the inner frame, do I need to run all new lines and eliminate the dist block? I’m attaching pics of the kit along with the front disc brake lines In-Line sells, am I looking at this correctly? Can’t picture it in my head what I’m to replace and what can remain, front to rear brake line comes to mind. As that’s also in the dist block, what happens with that?

 

So you're converting from manual drums to power front disc? Obviously you'll need the lines from the M/C that are routed for power brakes. The more important question is, are you using the 1970 style metering valve system or the 1971-up combo valve? If you are using the 1970 system, you need the metering valve that goes under the M/C, which obviously requires different hard lines. The 1970 cars used the same distribution block on the frame as did drum-only cars. The 1970 cars did NOT use a proportioning valve (contrary to popular belief). Instead, the 1970 cars used different sized rear wheel cylinders to provide the correct front/rear balance.

Personally, I would suggest using the 1971-up combo valve, which replaces the distribution block on the frame and includes the metering valve as well as the proportioning valve. The down side is that the combo valve uses different size flare nuts in a couple of places. I'm pretty sure the line to the rear brakes won't fit without an adapter fitting, for example. Also keep in mind that unless you put the combo valve in exactly the same place as the factory valve, the pre-bent lines likely won't line up. You could also use the combo valve kit that mounts under the M/C, which gets it out of the way of headers, but then all bets are off on pre-bent lines.

 

If you're interested I have a complete set of original disc brakes lines from a low mileage 70 442 for $20 plus shipping. I bought them not realizing that I had a new set of stainless lines that had come with my car. They don't look exactly like the ones in the In-Line pic.

https://www.facebook.com/marketplace...9998018618259/

 

I have used the line set the OP posted. It is for a combo valve mounted under the master cylinder. There is no adapter available to connect the new rear line from the combo valve to the original rear line that connects to the frame mounted distribution block and runs the length of the car to the rear.

You have two options. Cut the original fitting off your existing line and install a new one or buy the complete conversion kit that has a new rear line with correct fitting from Inline tube.

I ran into the fitting size issue this past summer using the inline tube conversion line kit.