This query is in regards to my 1980 245. I had a reputable technician replace the engine with a B230 with my standard B21 head and manifolds, install a new ring set and bearing set. The engine has plenty of pep but a nasty habit of periodically (usually at higher Interstate speeds--65-70) of somehow blowing oil through the flame trap, fogging cars to the rear and depositing oil in the filter box. It will only happen for a short time, then clear exhaust. The technician cannot think of a reason for this activity but I am afraid I will be getting a citation if it happens at the wrong time. Anyone have any ideas what could be causing this phenomena? Thanks in advance.