hydraboost issues ???? help

[XcYZ]

I had a similar problem, it turned out that the new style PS pump that I'm now using is ultra sensitive to fluid level in the resevoir. It looks almost like it has too much fluid now and the foaming and noise went away.

As for the slow brake pedal return, that's almost certainly a backpressure issue on the assist unit discharge line. Are you running a T on the low pressure side? Is it oriented the right way? With my new style PS pump, there was so much flow on the low pressure side, it was backing up the discharge line and doing exactly the same thing you described. To fix this, I now have the assist unit discharging directly into the resevoir and not T'd into the low pressure side of the PS circuit.

Oh, and how do you spell resevoir? I know that's not right. lol