williamggruff in Arlington, VA Subject: Re: What is windage tray (crank scraper)?
When the crankshaft rotates, it sprays oil around the crank case. The oil that sprays up on the inner walls of the block reduces the volume of oil sitting in the bottom of the oil pan, thus reducing the volume of oil available to the oil pump. Also, if you look at the way your engine sits at an angle in the engine bay, you can imagine that taking a hard left turn will leave the oil pump with nothing to pump. A windage tray/crank scraper reduces the amount of excess oil that flies around the inner portion of the block when the crank rotates, and acts as a barrier to keep the oil from riding up the side of the block, thereby increasing the amount of oil available to the oil pump. It also reduces the amount of oil that rides around on the crankshaft, which frees up some power.
