I keep re-reading this post, and can't help but think about the little German sports car we did brakes on. We put bigger calipers on the front, put in a bigger MC, replaced all 4 rubber hoses (independent rear), and replaced all steel lines. We also replaced the proportioning valve with a simple tee, because the new front calipers were so much bigger.
The thing is, getting this working right was all about the bleeding. All the on-line experts were adamant about this: bleed the furthest caliper first...the right rear, then left rear, then right front, and finally, left front. And have a couple quarts of brake fluid on hand. Not that the system is so big, but if you don't get ALL the air out, you'll have some wierd issues. That compensation valve is a concern...
Oh, and having someone pump the pedal works better than any piece of bleeding equipment you can buy, except one. Get some speed-bleeders, and do it yourself!
If bleeding the ENTIRE SYSTEM doesn't cure this problem, I suspect those "new" front calipers.
cm
