Windage is a term that gets thrown around a lot, but it’s not always clearly defined. For instance, the windage tray has been broadened to encompass a couple different features in recent years. In many cases, the sheetmetal plate that goes over the opening of the sump, where it meets the body of the oil pan, has been called a windage tray. This is actually the anti-slosh baffle, which is designed to keep the oil contained in the sump so that it does not get back into the rotating assembly. The windage tray itself is the screen or louvered piece that is either mounted directly to the main caps of the engine, or in the oil pan itself, and usually has an integrated crank scraper. At Moroso, our oil pan and windage tray designs live and die by our in-house dyno, track testing, and our network of top engine builders and racers who we use to test our products. We feel windage trays are important in a high-performance oiling system. Some engines and oil pans can benefit more from windage trays than others. Engines that are static and employ big box oil pans—which keeps the oil away from the crank—and have a conservative rod and stroke combination are not as prone to windage. The same goes for engines that are operated in an rpm range that is less than 5,500. Conversely, a long-stroke, high-rpm engine with a small oil pan that is put through acceleration, deceleration, right turns, left turns, and quick up and down movements is more prone to windage. We have seen and heard of windage trays freeing up to 5 percent more horsepower on these types of engines. Also, a windage tray can help with oil temperature and pressure. How? By keeping oil off the crank so that it does not froth the oil, and put extra heat into it.
With the growing popularity of Pro Touring muscle cars and open track events, it’s not that uncommon to run into a racer in the pits who has suffered some kind of oil starvation issue. Several techniques can be used when designing an oil pan to address this. The oil pans that we produce for road race and autocross applications have a sump that is shaped like an upside down “T”. This shape serves many functions. It allows extra oil capacity without the sump being too deep, since road race and autocross cars like being lower to the ground for handling and braking purposes. Inside a proper road race oil pan there is trapdoor baffling, which are hinged pieces of sheetmetal that open up to a 45-degree angle during acceleration, cornering, and, in some cases, braking. These trapdoor baffles are attached to sheetmetal dividers. As a result, during hard acceleration a trapdoor baffle will swing open and release a pocket of oil that has been held back by the divider. The released oil then feeds the oil pump pickup without a disruption in oil flow. The sides of the sumps that tee out are called wings, and they also hold pockets of oil that are held by trapdoor baffling in each side. When a car that is equipped with the road race oil pan takes hard right or left turns, the trapdoor on the opposite side opens up and releases oil to feed the oil pump pickup. When the trapdoor closes, the reserve of oil builds back up to be ready for the next time that it is needed. For 2011, Moroso introduced a line of road race oil pans for C3 and C4 Corvettes, as well as other low ground clearance applications. This the first line of road race oil pans on the market that will clear a 4.125-inch stroke with most steel rods. In the coming months, Moroso Performance Products will be expanding our line of multi-baffled oil pans.