No brakes after rear disc swap [NON FESTIVA]

[Flw Sock]

I swapped the rear end on my Dakota with a newer model with rear disc brakes. I have the brake lines ran and everything seemed to be fine, and the brakes are all bled to perfection. However, when I try to use the brakes, there's barley anything there. Is there something else I have to do when I do the disc conversion? Everything else in the brake system is stock. Does anybody know what my problem is? Please let me know so I can fix it!

Thanks everybody,
Karl G.

[FestYboy]

Did you replace the master cylinder for a 4 wheel disc unit? The rear calipers use more fluid than wheel cylinders.

[Flw Sock]

No, the only thing that was changed was the rear end, and I attached new brake lines to the rear. I was told I didn't need to change the master (I made sure to ask), is this incorrect?

[FestYboy]

Yes. Your Dakota uses a 15/16" bore and the newer ones use a 1 1/8" bore. You need the extra capacity to fill the rear calipers.

[Flw Sock]

Do you have any idea as to if a newer style master will be a bolt on replacement?

[FestYboy]

No I don't, but it should be easy to figure out at your local mcauto parts store

[Flw Sock]

I was also just told that I would need an adjustable proportioning valve. Is this true?

[FestYboy]

You should use the proportion block from the donor