Factory disc question for those with stock disc brakes. NOT aftermarkets

63Tigerlily said

So here you can see the valve from doctor dif. The only difference from his diagram is that I use one front circuit to feed the original block that splits into two front circuits.
This was only to get it going temporarily. One of the original nuts of the front circuit rounded off.
I still don’t see, once bled, why this would cause a soft pedal.View attachment 1716428016

Click to expand...

The newer block is a distribution block ONLY. Proportioning is done by the master cylinder. There is a balance check valve in the fronts to equalize pressure right to left. By routing from one side only the check valve is shutting off the side where all of the flow is going. (Your front brakes)
Route the brake lines to use distribution in the new block.