I recently brought home all of the original 1956-vintage factory PCV system from a 235 engine at a salvage yard. I have similar engines retrofitted into 3 earlier trucks. The shop manual info about keeping the misc plumbing clean is pretty straight forward. But I'm unclear what the advantages of PCV vs. road draft tube were as viewed through the perspective of the time. Strictly to reduce pollution? Improve mileage? Increase power? Would I need to re-jet the carb to accomodate increased airflow if I went this route? I would appreciate the feedback of anyone who has done this to determine if this system is worth adding to an engine or not. Thanks! Dave

1946 Chevy pickup, 1948 Chevy suburban, 1950 Chevy pickup, 1952 GMC pickup, 1957 Chevy pickup, 1939 Chevy pickup