Had same issue after rebuild. HG had small leak, no white smoke, no oil mixture, it would do so after I would drive about 80 miles on the interstate. I took the valve cover off and re toqued the inner 6 bolts to 90ft/lb and the outer to 80 ft/lbs night and day improvement (useing mls HG)
Outside of Corona: "That sucks, peace out..." (jamie walks away)... "Sweeet, what we doin?" -Zac Tim's garage (prior to motor install): "Im gonna smoke real quick, that way if you fuck up I am already nicotined up" -Tim