8.8 proportioning valve?

So I did the 8.8 and now my rear braking is lacking. I am still using the stock valve for the old drums. The problem is now my front brakes lock up on hard braking which is dangerous and scary. Does anyone know which valve will work with this setup?

im usin one off of a grand cherokee that had 4w disks.

x2, I have helped with a few of these 8.8 swaps and we installed the prop valve from the ZJ's that had rear disks and worked like a charm.