1 00:00:00,160 --> 00:00:02,920 Speaker 1: Streaming TV shows and movies directly to your home is 2 00:00:02,920 --> 00:00:05,680 Speaker 1: a breeze with Netflix. As a Netflix member, you can 3 00:00:05,720 --> 00:00:09,600 Speaker 1: instantly watch TV and movies on your PC, mac, mobile device, 4 00:00:09,720 --> 00:00:12,319 Speaker 1: or right on your television. Get a free thirty day 5 00:00:12,320 --> 00:00:15,840 Speaker 1: trial membership. Go to Netflix dot com slash brain Stuff 6 00:00:15,840 --> 00:00:19,160 Speaker 1: and sign up today. Welcome to brain Stuff from house 7 00:00:19,160 --> 00:00:30,480 Speaker 1: stuff works dot com where smart happens. Hi'm Marshall Brain 8 00:00:30,520 --> 00:00:35,080 Speaker 1: with today's question. What makes Nascar engines different from street 9 00:00:35,120 --> 00:00:39,400 Speaker 1: car engines. It's pretty obvious that Nascar engines and street 10 00:00:39,440 --> 00:00:43,120 Speaker 1: car engines are different. For example, a typical Nascar engine 11 00:00:43,200 --> 00:00:47,360 Speaker 1: has something like seven horsepower, and you just don't normally 12 00:00:47,440 --> 00:00:50,360 Speaker 1: see that in a street car engine. But the fact 13 00:00:50,479 --> 00:00:53,320 Speaker 1: is that at the bottom, you know, at the very beginning, 14 00:00:53,800 --> 00:00:56,920 Speaker 1: these two types of engines start out in a very 15 00:00:57,000 --> 00:01:01,360 Speaker 1: similar way. A team starts building a Nascar engine with 16 00:01:01,440 --> 00:01:04,840 Speaker 1: a block and a cylinder head that's remarkably similar to 17 00:01:04,880 --> 00:01:07,840 Speaker 1: a street version of the same thing. For example, if 18 00:01:07,880 --> 00:01:10,840 Speaker 1: a team is building a Dodge engine, they would start 19 00:01:10,880 --> 00:01:14,280 Speaker 1: out with a block based on a three forty cubic 20 00:01:14,319 --> 00:01:17,399 Speaker 1: inch V eight engine design that was produced in the 21 00:01:17,480 --> 00:01:21,800 Speaker 1: nineteen sixties. The actual engine blocks and heads are not 22 00:01:22,000 --> 00:01:26,040 Speaker 1: made from the original tooling. They're actually custom made race 23 00:01:26,160 --> 00:01:29,200 Speaker 1: engine blocks, But they have some things in common with 24 00:01:29,240 --> 00:01:33,240 Speaker 1: the original engines. For example, they have the same cylinder bore, 25 00:01:33,360 --> 00:01:37,119 Speaker 1: center lines, the same number of cylinders, and the same 26 00:01:37,160 --> 00:01:41,560 Speaker 1: based displacement, And like the original nineteen sixties engines, the 27 00:01:41,640 --> 00:01:46,759 Speaker 1: valves are driven by push rods rather than by overhead camshafts. 28 00:01:46,760 --> 00:01:50,720 Speaker 1: But NASCAR engines do produce seven fifty horsepower, and they 29 00:01:50,760 --> 00:01:56,320 Speaker 1: do that without turbochargers, superchargers, or any particularly exotic components. 30 00:01:56,680 --> 00:01:59,680 Speaker 1: So how do they make all that power? Here are 31 00:01:59,720 --> 00:02:03,440 Speaker 1: some of the things that distinguish a NASCAR engine from 32 00:02:03,440 --> 00:02:08,960 Speaker 1: a regular engine. First, there's the displacement three cubic inches 33 00:02:09,040 --> 00:02:12,440 Speaker 1: or five point eight seven leaders. Not many cars have 34 00:02:12,680 --> 00:02:16,120 Speaker 1: engines this big anymore, but the ones that do usually 35 00:02:16,160 --> 00:02:19,400 Speaker 1: only generate about three hundred horsepower, so there's something else 36 00:02:19,480 --> 00:02:24,080 Speaker 1: besides displacement that's doing it. Second, the NASCAR engines have 37 00:02:24,360 --> 00:02:29,239 Speaker 1: extremely radical cam profiles, which open the intake valves much 38 00:02:29,280 --> 00:02:32,640 Speaker 1: earlier and keep them open longer than a street car 39 00:02:32,680 --> 00:02:36,399 Speaker 1: engine would. This allows more air to be packed into 40 00:02:36,400 --> 00:02:41,240 Speaker 1: the cylinders, especially at high speeds. Third, NASCAR engines use 41 00:02:41,520 --> 00:02:45,320 Speaker 1: massive carburetors that let in huge volumes of air and fuel. 42 00:02:45,720 --> 00:02:49,600 Speaker 1: There are no fuel injectors on these engines. Fourth, they 43 00:02:49,639 --> 00:02:54,880 Speaker 1: have extremely high intensity programmable ignition systems, so the spark 44 00:02:54,960 --> 00:02:59,320 Speaker 1: timing can be customized to provide the most possible power. Five. 45 00:03:00,000 --> 00:03:04,120 Speaker 1: All the subsystems like cooling pumps, oil pumps, steering pumps, 46 00:03:04,120 --> 00:03:08,200 Speaker 1: and alternators are designed to run at sustained high speeds 47 00:03:08,200 --> 00:03:10,799 Speaker 1: and temperatures, so the engine is gonna be able to 48 00:03:10,880 --> 00:03:14,880 Speaker 1: last through the race. Finally, when a NASCAR engine is assembled, 49 00:03:15,160 --> 00:03:19,200 Speaker 1: it's built to very exacting tolerances. The parts of machine 50 00:03:19,320 --> 00:03:23,600 Speaker 1: much more accurately than normal so that everything fits perfectly. 51 00:03:24,120 --> 00:03:27,880 Speaker 1: Cylinders are board to more exacting tolerances than street cars. 52 00:03:28,080 --> 00:03:31,880 Speaker 1: The crank chefts and other rotating parts are balanced. Making 53 00:03:31,919 --> 00:03:34,480 Speaker 1: sure that the parts are as close to their exact 54 00:03:34,520 --> 00:03:38,520 Speaker 1: dimensions as possible helps the engine achieve its maximum potential 55 00:03:38,600 --> 00:03:42,400 Speaker 1: power and also helps reduce wear. If the parts are 56 00:03:42,440 --> 00:03:45,320 Speaker 1: too big or too small, power can be lost due 57 00:03:45,360 --> 00:03:50,280 Speaker 1: to extra friction or pressure leakage through bigger than necessary gaps. 58 00:03:51,080 --> 00:03:53,880 Speaker 1: After the engine is assembled, it runs on a dynamometer 59 00:03:54,360 --> 00:03:57,200 Speaker 1: for thirty minutes to break it in. The engine is 60 00:03:57,280 --> 00:04:01,560 Speaker 1: then inspected, The filters are checked or excess metal filings 61 00:04:01,560 --> 00:04:04,960 Speaker 1: and any other signs of excessive wear. If it passes 62 00:04:05,080 --> 00:04:08,160 Speaker 1: this test, then it goes on the dynamometer for another 63 00:04:08,240 --> 00:04:12,160 Speaker 1: two hours. During this test, the ignition typing is dialed 64 00:04:12,160 --> 00:04:15,680 Speaker 1: in to maximize the power that the engine produces, and 65 00:04:15,720 --> 00:04:18,960 Speaker 1: the engine is cycled through various speed and power ranges. 66 00:04:19,480 --> 00:04:23,880 Speaker 1: After this test, the engine is again disassembled and inspected thoroughly. 67 00:04:24,400 --> 00:04:27,720 Speaker 1: The valve train is pulled and the camshaft and lifters 68 00:04:27,720 --> 00:04:31,360 Speaker 1: are expected. The insides of the cylinders are examined with 69 00:04:31,480 --> 00:04:34,960 Speaker 1: Boris scopes. The cylinders are pressurized and the rate of 70 00:04:35,040 --> 00:04:37,960 Speaker 1: leakdown is measured to see how well the pistons and 71 00:04:38,040 --> 00:04:42,000 Speaker 1: seals hold the pressure. All the lines and hoses are checked. 72 00:04:42,400 --> 00:04:45,919 Speaker 1: Only after all these tests and inspections are finished, is 73 00:04:45,960 --> 00:04:49,080 Speaker 1: the engine ready to go to the races. Ensuring the 74 00:04:49,160 --> 00:04:53,320 Speaker 1: reliability of the engine is critical. Almost any engine failure 75 00:04:53,400 --> 00:04:58,000 Speaker 1: during a race eliminates any chances of winning for moral 76 00:04:58,120 --> 00:05:00,840 Speaker 1: This and thousands of other topics at how staff works 77 00:05:00,880 --> 00:05:07,760 Speaker 1: dot com. Streaming TV shows and movies directly to your 78 00:05:07,760 --> 00:05:10,599 Speaker 1: home is a breeze With Netflix. As a Netflix member, 79 00:05:10,640 --> 00:05:13,960 Speaker 1: you can instantly watch TV and movies on your PC, mac, 80 00:05:14,080 --> 00:05:16,960 Speaker 1: mobile device, or right on your television. Get a free 81 00:05:17,000 --> 00:05:20,440 Speaker 1: thirty day trial membership. Go to Netflix dot com slash 82 00:05:20,440 --> 00:05:21,960 Speaker 1: brain stuff and sign up today.