Brake bias on an 86 4000 Quattro

[vrona@ix.netcom.com (Steven Verona)]

The brake bias on my 4kq is way out of wack.  The front wheels lock up 
way too early and the rear brakes are barely used.  Is there an 
adjustment that can be made to even out the balance?

I looked in the Bentley manual and it shows a pressure control set up 
below the master cylinder and it "says" it is not adjustable.  Is this 
true or is it "not adjustable" for liability reasons?

Thanks in advance.

Steven Verona