Are you saying that the fan blowing on the cylinders is sufficient for cooling in stop and go city driving? I am just trying to figure it out since I do not have a temp gauge on the car
Pretty much...the cooling for the cylinders is by heat transfer from the metal of the fins to the air so keeping a supply of air moving across the fins will keep the heat transfer going. If you were to have a fan behind the cylinders trying to suck air through the fins you would need to fit really well sealed ducting or the air would be drawn by the easiest route to the fan rather than through the fins; basically its easy to direct a jet of air blowing into nooks and crannies but damn near impossible to choose where air is being drawn from once you're a very short distance from the air inlet face.
Way back, Suzuki had a family of oil cooled engines which had oil jackets similar to the water jackets that all water cooled engines have and enormous oil coolers that were often supplemented by additional coolers on tuned engines. Our engines don't have anything like those jackets, most if not all of the oil just goes through the push rod tubes so is effectively external to the cylinders.
In a hot climate and with lots of stop start, crawling traffic, a small fan cooled oil cooler with a really quite high temperature thermostat on it may well be beneficial but I don't believe that the large oil coolers mounted in the breeze with no fan assist do much good at all. The engines cool adequately when at speed and you need quite high temperatures in the oil to keep it in good condition.
Where I live, high temperatures and crawling traffic aren't a problem!
