1 00:00:00,160 --> 00:00:03,440 Speaker 1: Audible dot com is the leading provider of downloadable digital 2 00:00:03,480 --> 00:00:07,160 Speaker 1: audio books and spoken word entertainment. Audible has over one 3 00:00:07,200 --> 00:00:10,080 Speaker 1: hundred thousand titles to choose from to be downloaded to 4 00:00:10,119 --> 00:00:13,640 Speaker 1: your iPod or MP three player. Go to audible podcast 5 00:00:13,760 --> 00:00:16,120 Speaker 1: dot com slash brain stuff to get a free audio 6 00:00:16,160 --> 00:00:18,560 Speaker 1: book download of your choice when you sign up today. 7 00:00:19,480 --> 00:00:31,520 Speaker 1: Welcome to Brainstuff from hastaff works dot com where smart happens. Hi. 8 00:00:31,560 --> 00:00:35,320 Speaker 1: I'm Marshall Brain with today's question. Why do some engines 9 00:00:35,560 --> 00:00:40,479 Speaker 1: use a dry sump oil system? Most production cars have 10 00:00:40,720 --> 00:00:44,120 Speaker 1: a wet sump oil system. The oil that you put 11 00:00:44,120 --> 00:00:47,360 Speaker 1: into the engine is stored beneath the crankshaft in the 12 00:00:47,360 --> 00:00:50,479 Speaker 1: oil pan. This pan has to be large enough and 13 00:00:50,560 --> 00:00:53,240 Speaker 1: deep enough to hold four to six quarts of oil. 14 00:00:53,640 --> 00:00:56,560 Speaker 1: Think about two three liter bottles of soda and you 15 00:00:56,600 --> 00:00:59,280 Speaker 1: can see that this storage area can be pretty big. 16 00:01:00,080 --> 00:01:03,240 Speaker 1: A wet sump, the oil pump sucks oil from the 17 00:01:03,240 --> 00:01:05,640 Speaker 1: bottom of the oil pan through a tube and then 18 00:01:05,760 --> 00:01:08,080 Speaker 1: pumps it to the rest of the engine. In a 19 00:01:08,240 --> 00:01:12,440 Speaker 1: dry sump, extra oil is stored in a tank outside 20 00:01:12,440 --> 00:01:15,360 Speaker 1: the engine rather than in the oil pan. There are 21 00:01:15,400 --> 00:01:18,520 Speaker 1: at least two oil pumps in a dry sump system, 22 00:01:18,640 --> 00:01:21,520 Speaker 1: one polls oil from the sump and sends it to 23 00:01:21,560 --> 00:01:24,039 Speaker 1: the tank, and the other takes oil from the tank 24 00:01:24,120 --> 00:01:27,119 Speaker 1: and sends it to lubricate the engine. The minimum amount 25 00:01:27,160 --> 00:01:31,400 Speaker 1: of oil possible remains in the engine. Dry sump systems 26 00:01:31,440 --> 00:01:35,920 Speaker 1: have several important advantages over wet sums. First, because of 27 00:01:36,040 --> 00:01:38,759 Speaker 1: dry sump doesn't need to have an oil pan big 28 00:01:38,880 --> 00:01:41,640 Speaker 1: enough to hold the oil under the engine, the main 29 00:01:41,800 --> 00:01:44,400 Speaker 1: mass of the engine can be placed lower in the vehicle. 30 00:01:44,880 --> 00:01:47,440 Speaker 1: This helps lower the center of gravity of the engine 31 00:01:47,520 --> 00:01:51,000 Speaker 1: and can also help aerodynamics by allowing a lower hoodline. 32 00:01:51,560 --> 00:01:54,000 Speaker 1: The oil capacity of a dry sump system can be 33 00:01:54,040 --> 00:01:56,760 Speaker 1: as big as you want. The tank holding the oil 34 00:01:56,800 --> 00:01:59,680 Speaker 1: can be placed anywhere on the vehicle. In a wet 35 00:01:59,720 --> 00:02:03,800 Speaker 1: sud ump, turning, breaking and acceleration can cause the oil 36 00:02:03,840 --> 00:02:07,400 Speaker 1: to pool on one side of the engine. This sloshing 37 00:02:07,480 --> 00:02:10,560 Speaker 1: can dip the crank shaft into the oil as it turns, 38 00:02:10,720 --> 00:02:14,160 Speaker 1: or it can uncover the pumps pick up to excess 39 00:02:14,200 --> 00:02:16,720 Speaker 1: oil around the crank shaft in a wet sump can 40 00:02:16,760 --> 00:02:19,840 Speaker 1: get on the shaft and cut horse power. Some people 41 00:02:19,919 --> 00:02:23,200 Speaker 1: claim improvements of as much as fifteen horse power by 42 00:02:23,240 --> 00:02:26,440 Speaker 1: switching to a dry sump. The disadvantage of the dry 43 00:02:26,480 --> 00:02:30,840 Speaker 1: sump system is the increased weight, complexity, and cost from 44 00:02:30,880 --> 00:02:34,120 Speaker 1: that extra pump and the tank itself, but that's a 45 00:02:34,200 --> 00:02:37,840 Speaker 1: small price to pay for such big benefits. Do you 46 00:02:37,840 --> 00:02:41,200 Speaker 1: have any ideas or suggestions for this podcast? If so, 47 00:02:41,400 --> 00:02:44,080 Speaker 1: please send me an email at podcast at how stuff 48 00:02:44,120 --> 00:02:46,880 Speaker 1: works dot com. For more on this and thousands of 49 00:02:46,880 --> 00:02:50,040 Speaker 1: other topics, go to how stuff works dot com and 50 00:02:50,080 --> 00:02:52,240 Speaker 1: be sure to check out the brain stuff blood on 51 00:02:52,320 --> 00:02:58,440 Speaker 1: the house stuff works dot com home page. Streaming TV 52 00:02:58,520 --> 00:03:00,840 Speaker 1: shows and movies directly to your home is a breeze 53 00:03:00,840 --> 00:03:03,880 Speaker 1: with Netflix. As a Netflix member, you can instantly watch 54 00:03:03,919 --> 00:03:07,440 Speaker 1: TV and movies on your PC, mac, mobile device, or television. 55 00:03:07,760 --> 00:03:10,720 Speaker 1: Get a free thirty day trial membership. Go to Netflix 56 00:03:10,760 --> 00:03:12,800 Speaker 1: dot com slash stuff and sign up today.