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Speaker 1: Welcome to Brainstuff from hastaff works dot com where smart happens. Hi.
Speaker 1: I'm Marshall Brain with today's question. Why do some engines
Speaker 1: use a dry sump oil system? Most production cars have
Speaker 1: a wet sump oil system. The oil that you put
Speaker 1: into the engine is stored beneath the crankshaft in the
Speaker 1: oil pan. This pan has to be large enough and
Speaker 1: deep enough to hold four to six quarts of oil.
Speaker 1: Think about two three liter bottles of soda and you
Speaker 1: can see that this storage area can be pretty big.
Speaker 1: A wet sump, the oil pump sucks oil from the
Speaker 1: bottom of the oil pan through a tube and then
Speaker 1: pumps it to the rest of the engine. In a
Speaker 1: dry sump, extra oil is stored in a tank outside
Speaker 1: the engine rather than in the oil pan. There are
Speaker 1: at least two oil pumps in a dry sump system,
Speaker 1: one polls oil from the sump and sends it to
Speaker 1: the tank, and the other takes oil from the tank
Speaker 1: and sends it to lubricate the engine. The minimum amount
Speaker 1: of oil possible remains in the engine. Dry sump systems
Speaker 1: have several important advantages over wet sums. First, because of
Speaker 1: dry sump doesn't need to have an oil pan big
Speaker 1: enough to hold the oil under the engine, the main
Speaker 1: mass of the engine can be placed lower in the vehicle.
Speaker 1: This helps lower the center of gravity of the engine
Speaker 1: and can also help aerodynamics by allowing a lower hoodline.
Speaker 1: The oil capacity of a dry sump system can be
Speaker 1: as big as you want. The tank holding the oil
Speaker 1: can be placed anywhere on the vehicle. In a wet
Speaker 1: sud ump, turning, breaking and acceleration can cause the oil
Speaker 1: to pool on one side of the engine. This sloshing
Speaker 1: can dip the crank shaft into the oil as it turns,
Speaker 1: or it can uncover the pumps pick up to excess
Speaker 1: oil around the crank shaft in a wet sump can
Speaker 1: get on the shaft and cut horse power. Some people
Speaker 1: claim improvements of as much as fifteen horse power by
Speaker 1: switching to a dry sump. The disadvantage of the dry
Speaker 1: sump system is the increased weight, complexity, and cost from
Speaker 1: that extra pump and the tank itself, but that's a
Speaker 1: small price to pay for such big benefits. Do you
Speaker 1: have any ideas or suggestions for this podcast? If so,
Speaker 1: please send me an email at podcast at how stuff
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