thats the exact same problem I was having... In fact, I posted about it a couple times, but didn't get any help...

I was running F/R integra brakes (w/ brembo rotors, axxis ultimate, ss lines, not that that really matters) and when I put on the booster and MC is when I started having the problem (the 13/16MC and civic booster worked fine, just felt like shit). I was using a brand new 15/16MC, and a *mystery* (he said 95 gsr, but who knows) integra booster from some random guy on hondaclassifieds.com (don't ever buy anything there) when I had the problem. I'm assuming the booster was faulty because thats the only part in the whole braking system that wasn't brand new :dunno:

I just put the 13/16 and civic booster back on, and when I get a day off, I'll try and figure out whats wrong.