the bearing that the passenger side axle goes into. that bolts to the block? carrier bearing maybe?
and would this cause a thumping noise whenever not on the throttle, or when hitting the brakes, in neutral, and in gear?
don't think that is the problem, but is always a possibility. i have worked on many b13s with sr20 including my three and have never seen a bad bearing carrier. do you get a pulsation in the bake pedal?