Yes, it drains better with oil pressure in the canister, and I just confirmed that the filter drain fitting does intersect the output of the oil distributor on a 216 or an early 235 as it heads for the dipper spray tubes. That will slow down the flow a little because there will be some back pressure against the drain. A very simple method to get better flow through the filter without any permanent modification to the block would be to braze a 1/8" pipe coupling into the side of the oil pan about 1" below the pan rail and attach the drain line there. This would accomplish the same oil flow as a bypass filter on a 235, which does drain directly back to the pan. The orfice in the filter standpipe would control the flow regardless of the diameter of the flex hose or the fitting added to the pan. Then the purists won't break out in a terminal case of hives for desecrating a piece of 70-year-old cast iron! LOL!
Fitting a full-circle rear main bearing lip seal at the back of the block will really get the oldtimers in a phase 10 panic! I can do that with my cylinder boring bar, and the rear main seal for a Ford Diesel V8 is an exact fit!
Jerry
