hehe, i'm pretty sure that i qualified my statement by saying that i learned the sump baffle trick from the old guys when i was a young guy.
the old guys i knew pretty much invented cars.
i had to pull out the stops for thermal management to keep my turbo3 project engine from burning up. one of the things i found was that the factory fan is woefully lacking for an engine with even a modest increase in hp from stock. even the cowling doesn't perform well. i run 12" 1650 cfm fans that mount directly to the radiator core. i also run a chinese made 2" core fabricated aluminum radiator which improves engine cooling.
the entire front side of the engine bay is taken up by the radiator and water to air intercooling heat exchanger, the heat exchanger running the same 12" 1650 cfm fan albeit speed controlled by my megasquirt using a temp vs fan speed process control algorithm that maintains 98 f on the intercooler output tank up to full boost pressure of 21 psi with ambient air temps under 90 f. i designed provisions for the a2w circulation pump to be speed controlled as well but i don't use that feature and let the pump run at it's peak curve.
on the oil pump i started out using a 20 row cooler and eventually scaled back to a 9 row that runs fairly steady state without cycling the thermostat in the oil adapter. the oil temp t-stat is something that i omitted from my lil' black monster turbo3 engine which uses the turbine tech gen 1 upgrade kit including the remote filter adapter that jard made for the kit.
oil pressure itself is controlled as much by the 55 psi control spring in the oil pump's pressure relief valve as it is by the oiling system itself. at 55 psi the valve lifts and dumps oil directly back into the sump. bearing wear, seal degradation, and deposits/ blockages in the passageways all contribute to lower volumetric flow but the system pressure won't exceed 55 psi unless there is a problem with the over pressure valve. the oil internal galley runs from the over pressure valve through the block to the oil filter boss. through the filter and into the passageway where the oil pressure switch lives and then through internal passageways to the various oiling points.
i purposely used 12mm diameter hoses with smooth bore a-n fittings to the oil cooler filter set at the rear of the lower engine bay, back to the oil cooler in the front, and then back to the filter adapter to maximize the volume of the oil cooler/ remote filter system. it added 2 quarts to the oil volume.
don't underestmate to amount of work it is to construct a good gated baffle in a suzuki oil pan. the construction is best done using a tig welder, something i don't have in my kit. borrowing time on a tig machine for me is sort of hard these days. and because i'm an old bastard my eyes aren't all they used to be.
on my twincam vert i used the same aluminum radiator, fan, and hose set. because i run the oem ecu with an upgraded eeprom i use an outboard adjustable fan speed control unit made by spal. it has adjustable lower and upper temperature settings. when coolant temp reaches the lower set point the controller applies full voltage to spin the fan up and then drops to 50% speed. as coolant temp moves up to the higher temp set point the fan speed increases linearly up to 100% at the upper temp setting. i set the low point at 160* f, the t-stat is rated at 192* f, and i set the upper point at 200* f. it works like a charm and rarely runs the fan at full boogey.
on non-air conditioned models the factory used a stamped steel panel screwed at 4 points to the upper and lower radiator supports that block air to create a high pressure zone directly in front of the engine radiator. on the upright brace in the center of the upper and lower radiators supports they used a thin plastic bit that made a smooth, contoured transition point to flow air blocked on the right side through the radiator on the left side. conversely, the back side of the panel directly in front of the engine becomes a low pressure zone which directs flow up into the engine bay across the top of the engine, and then down the firewall where it merges with air flowing under the car. that was part of the reason the bottom the firewall kicks back, to merge air.
early on when i was playing with these cars i instrumented the engine bay with thermocouples connected to a data scanner to measure air temps under the hood while driving the car to develop air flow models. as an engineer i have always admired suzuki's all but invisible design tweaks. the thermal dynamics of the engine bay design are impressive at at 30 mph the under hood temps are within a degree f of ambient temps.
i see a lot of race cars that have blocked up the front bodywork to gain some aerodynamic advantage. typically, that sort of modification would create an even lower pressure under the car. that would increase delta pressure between the high pressure zone in front of the radiator and the low pressure zone where entrainment occurs at the bottom of the firewall. unfortunately, the air dam kills the intermediate pressure zone in front of the engine behind the blocking panel. that area becomes a quieted area that doesn't work very well to wick away engine heat at the exhaust manifold and off the valve cover. i have always thought that a modified naca duct on the right side of the hood towards the front corner of the hood would help thermal management.
anyway, one of the first things that crosses my mind with race cars is the probability of stagnant air flow in the engine bay causing heat soak problems.
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