Proportioning valve

right now the brakes feel like the rear sets down first before the front as the rear drops before the nose dips. hope this explanes it ok.
It does explain it ok. What are the tire sizes?
Mine does the same, because
I set it up that way,because
my car has 295s in the back, and 235s in the front.
If I had same size tires on the rear, the rear tires could/would, lock up first. And if/when that happens, then there is no way to keep the back in the back, and it usually spins you out.
But with bigger tires in the back, it is nearly impossible, on my car, to lock the rears first, so it is as you say, like throwing a parachute out the back, as the rear seems to drop microseconds earlier.
I gutted my P-valve as a test, and when it worked like this, I left it like that, and swapped in different wheel cylinders for fine tuning.I like it, but it was a lil unnerving at first.