# Downshifiting a Manual Automobile to Slow Down **URL:** \ **Category:** Factual Questions\ **Created:** [May 3, 2006, 12:03am UTC](https://boards.straightdope.com/t/downshifiting-a-manual-automobile-to-slow-down/355170 "2006-05-03T00:03:00Z")\ **Posts on this page:** 20\ **Page:** 3
**Author:** ![Dog80](https://avatars.discourse-cdn.com/v4/letter/d/6bbea6/32.png) [@Dog80](https://boards.straightdope.com/u/Dog80)\ **Post date:** [May 3, 2006, 7:21pm UTC](https://boards.straightdope.com/t/downshifiting-a-manual-automobile-to-slow-down/355170/41 "2006-05-03T19:21:11Z")
> [@commasense](#): > > > [@Dog80](#): > > > > I think he is downshifting one gear at a time, hence the several blips of the throttle (eg. he goes from 4th to 3rd and then to 2nd instead of going directly from 4th to 2nd). > > Maybe, and if so, he’s not a very good driver. But I don’t think that’s what he’s doing. I watched the video again. Now I am 100% positive that this is exactly what he does. Bad driving? I wouldn’t say so. The drivers on the Best Motoring show do the same thing when approaching a corner. I believe they do this because you can’t rev the engine high enough to synchronise for a two-gear downshift so you have to do it one gear at a time. > [@commasense](#): > > > [@Dog80](#): > > > > Also keep in mind that this Ferrari has probably a non-synchronised gearbox, so heel-and-toe is the only way to downshift. > > You’re thinking of [double-clutching,](http://en.wikipedia.org/wiki/Double_clutch) which is not the same as heel-toe. No, double cluthing is the easy way to downshift but heel-and-toe is the most efficient. Besides, you can’t double clutch and brake at the same time. ---
**Author:** ![Dog80](https://avatars.discourse-cdn.com/v4/letter/d/6bbea6/32.png) [@Dog80](https://boards.straightdope.com/u/Dog80)\ **Post date:** [May 3, 2006, 7:24pm UTC](https://boards.straightdope.com/t/downshifiting-a-manual-automobile-to-slow-down/355170/42 "2006-05-03T19:24:42Z")
About the tire squealing: Remember, it is the 1970s! The tires of a modern econo-box can outperform those ultra high performance tires from the seventies. ---
**Author:** ![pulykamell](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/pulykamell/32/3166_2.png) [@pulykamell](https://boards.straightdope.com/u/pulykamell)\ **Post date:** [May 3, 2006, 7:28pm UTC](https://boards.straightdope.com/t/downshifiting-a-manual-automobile-to-slow-down/355170/43 "2006-05-03T19:28:05Z")
> [@commasense](#): > > Maybe, and if so, he’s not a very good driver. But I don’t think that’s what he’s doing. > You’re thinking of [double-clutching,](http://en.wikipedia.org/wiki/Double_clutch) which is not the same as heel-toe. Well, presumably he would be heel-and-toe double-clutching, wouldn’t he? I mean, he’s braking and double clutching at the same time, and the only way to accomplish this is heel-and-toe. Unless heel-and-toe means something else to you. Otherwise, I agree with everything else you’ve said. It’s only a personal anecdote, but I have asked professional performance drivers about this (I used to photograph for several car magazines, including Car and Driver), and they uniformly say the same thing: the brakes are to slow down, the shifting is for acceleration. ---
**Author:** ![Santos\_L\_Halper](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/santos_l_halper/32/1_2.png) [@Santos\_L\_Halper](https://boards.straightdope.com/u/Santos_L_Halper)\ **Post date:** [May 3, 2006, 7:46pm UTC](https://boards.straightdope.com/t/downshifiting-a-manual-automobile-to-slow-down/355170/44 "2006-05-03T19:46:10Z")
> [@js\_africanus](#): > > Okay, so my manual says shift up & down at 15mph, 25mph, 40mph, & 45mph. If I’m going fifity and need to brake, I apply my brakes. When the car slows to 45mph, I push down on the clutch; shift from fifth to fourth; and quick hit the accelerator with the side of my foot so that when I release the clutch in fourth gear, the rpm & speed properly match for that gear. Is that it? > > Ostensibly (and skepticism aside), the driver is supposed to be doing that in the movie. He would be braking with the clutch out, then push it in, shift & blip, then let it out again, all without taking his foot off the gas. Is that about right? Yes, that’s about right. It’s a bit difficult to follow reading about it though. Having someone who knows how to do it and practicing it yourself make it clearer what’s going on. Also, many cars don’t have the pedals set up very well to be able to double-clutch and heel-toe easily. **commasense** will be able to talk about it in more detail than I can. As for participating in a HPDE, I highly reccommend it. They’re loads of fun and teach you to be a better driver (both on the track and day-to-day on the road). I must warn you however that they can be addictive. I’ve known more than one person who started out attending one driving school and the next thing I knew they were spending every weekend autocrossing or seeing how much it’d cost them to pick up a dedicated track car. 🙂 ---
**Author:** ![Absolute](https://avatars.discourse-cdn.com/v4/letter/a/b2d939/32.png) [@Absolute](https://boards.straightdope.com/u/Absolute)\ **Post date:** [May 3, 2006, 8:00pm UTC](https://boards.straightdope.com/t/downshifiting-a-manual-automobile-to-slow-down/355170/45 "2006-05-03T20:00:37Z")
> [@Dog80](#): > > No, double cluthing is by the easy way to downshift but heel-and-toe is the most efficient. Besides, you can’t double clutch and brake at the same time. Every time this topic comes up, it seems like everyone has a different idea of the terminology. Double-clutching not the easiest way to downshift, and you can certainly double-clutch and brake at the same time - that’s what heel-and-toeing is. Here’s my understanding of what all the terms mean, and I’m pretty sure I’m right. **Single-clutched, non-rev-matched downshift** Foot off the gas, clutch in, move the shifter into gear, clutch out. Places a lot of wear on the clutch, because you’re using it to bring the engine up to speed. For people who would rather be driving automatics. **Single-clutched, rev-matched downshift** Foot off the gas, clutch in, move the shifter into gear and blip the throttle, clutch out. Matches the speed of the engine with the speed of transmission, no wear on the clutch. However, you place wear on the synchronizers in transmission, because when you move the shifter they have to accelerate the transmission to the speed of the wheels. **Double-clutched, rev-matched downshift** Foot off the gas, clutch in, move the shifter into neutral, clutch out, blip the throttle, clutch in, move the shifter, clutch out. No wear on the clutch, no wear on the synchronizers, because by shifting to neutral and blipping the engine you accelerate the transmission to the speed of the wheels. This is necessary in older cars, that didn’t have synchronizers. You can get away without it in newer cars, but I still do it when I’m jumping down several gears at once . You can feel the difference: the shifter just _slides_ in, while otherwise it would require a bit of force. **Heel-toe downshift** Either a single-clutched or double-clutched downshift, except you’re braking at the same time. This requires your right foot to press the brake pedal and blip the throttle simultaneously. The name is misleading - I don’t know of anyone who actually does this with their heel on the brake, and toes on the gas. I keep my foot vertical and just use the left half on the brake, right half on the gas. Anyone disagree? ---
**Author:** ![pulykamell](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/pulykamell/32/3166_2.png) [@pulykamell](https://boards.straightdope.com/u/pulykamell)\ **Post date:** [May 3, 2006, 8:18pm UTC](https://boards.straightdope.com/t/downshifiting-a-manual-automobile-to-slow-down/355170/46 "2006-05-03T20:18:13Z")
> [@Absolute](#): > > Every time this topic comes up, it seems like everyone has a different idea of the terminology. Double-clutching not the easiest way to downshift, and you can certainly double-clutch and brake at the same time - that’s what heel-and-toeing is. > > Here’s my understanding of what all the terms mean, and I’m pretty sure I’m right. > > **Single-clutched, non-rev-matched downshift** > Foot off the gas, clutch in, move the shifter into gear, clutch out. Places a lot of wear on the clutch, because you’re using it to bring the engine up to speed. For people who would rather be driving automatics. > > **Single-clutched, rev-matched downshift** > Foot off the gas, clutch in, move the shifter into gear and blip the throttle, clutch out. Matches the speed of the engine with the speed of transmission, no wear on the clutch. However, you place wear on the synchronizers in transmission, because when you move the shifter they have to accelerate the transmission to the speed of the wheels. > > **Double-clutched, rev-matched downshift** > Foot off the gas, clutch in, move the shifter into neutral, clutch out, blip the throttle, clutch in, move the shifter, clutch out. No wear on the clutch, no wear on the synchronizers, because by shifting to neutral and blipping the engine you accelerate the transmission to the speed of the wheels. > > This is necessary in older cars, that didn’t have synchronizers. You can get away without it in newer cars, but I still do it when I’m jumping down several gears at once . You can feel the difference: the shifter just _slides_ in, while otherwise it would require a bit of force. > > **Heel-toe downshift** > Either a single-clutched or double-clutched downshift, except you’re braking at the same time. This requires your right foot to press the brake pedal and blip the throttle simultaneously. The name is misleading - I don’t know of anyone who actually does this with their heel on the brake, and toes on the gas. I keep my foot vertical and just use the left half on the brake, right half on the gas. > > Anyone disagree? This is exactly how I know the terms, except that I guess I’ve never thought about single-clutch heel-and-toeing. When I say “heel-and-toe” I mean “heel-and-toe double clutch.” ---
**Author:** ![Santos\_L\_Halper](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/santos_l_halper/32/1_2.png) [@Santos\_L\_Halper](https://boards.straightdope.com/u/Santos_L_Halper)\ **Post date:** [May 3, 2006, 8:31pm UTC](https://boards.straightdope.com/t/downshifiting-a-manual-automobile-to-slow-down/355170/47 "2006-05-03T20:31:36Z")
Here’s a [map of the course](http://supergreg.hopto.org/carmovies/images/map.jpg), and a corresponding [map of Paris](http://travel.yahoo.com/p-travelguide-577412-map_of_paris-i). > [@hammos1](#): > > Those charts are wrong. The distance/time chart shows a relatively constant velocity, which doesn’t correspond to the other chart. That chart (the one in the upper right) Is anything but relatively constant. It’s divided up into eighteen segments. The steeper the rise, the faster he’s going in that segment. If he came to a complete stop, that segment would be horizontal. (I presume if he were to reach the speed of light, the line would be vertical :)) The last four segments (which make up nearly a quarter of the time) are much, much shallower than the earlier segments. The two steepest are segments six and seven, which match the other chart as the point where he reaches his highest speed. > [@](#): > > The portion of the film that shows the run between Etoile and Concorde is from about 1 min 30s to 2 min 30s- Etoile is where the Arc de Triomphe is (the large arch), and Concorde is the large square with a small obelisk in the middle. This is the only part of the journey where a speed of 150mph looks at all possible, but the speed is never much above 70mph. I disagree. Yes, it’s long and straight but there are lots of cross streets, red lights to run and potential cross traffic to watch out for. The section right after that, along the Jardin des Tuileries until he turns through the Lourve is straight without cross streets and he gets up to a higher speed there. From that point until the end he’s zig zagging through narrow streets (and more than once coming nearly to a stop because of other vehicles). Those sections he’s going much slower. > [@](#): > > The entire journey is about 6.5 miles and takes about 8 minutes- average speed is about 48mph. Their calculations are just over seven miles and seven and a half minutes for an average of 56.5 mph, pretty much the same numbers as yours. But you’re thinking he stayed much closer to that average than I do. He only hit his high speed for one brief point. Most of the rest of the first three quarters of the drive he’s avgeraging about 40-50 mph (again, only an average. His speed goes up and down quite a bit). The last quarter of the film he’s going much slower than that. ---
**Author:** ![sunacres](https://avatars.discourse-cdn.com/v4/letter/s/4491bb/32.png) [@sunacres](https://boards.straightdope.com/u/sunacres)\ **Post date:** [May 3, 2006, 8:31pm UTC](https://boards.straightdope.com/t/downshifiting-a-manual-automobile-to-slow-down/355170/48 "2006-05-03T20:31:49Z")
> [@Dog80](#): > > A throw out bearing costs about 5 dollars, so it is prudent to replace it just in case. So let me see if I’ve got this right: Case 1. Operator shifts perfectly every time, clutch plates are always exactly in synch and never wear out. But the throw-out bearing will, eventually, so this driver should put the car in neutral and let out the clutch when at idle to keep expensive clutch work at a minimum. Case 2. Operator doesn’t match engine and tranny speeds well, pops the clutch on take-off, and is generally abusive. This driver might as well depress the clutch at stop lights because their clutch plates will be shot soon anyway and replacing the throw-out bearings adds little to the cost of the operation. Case 3. (Me) Operator rarely thinks he’s Dan Gurney, but doesn’t shift perfectly every time, experiences “normal” wear on the clutch plates which will have to be replaced sooner or later. The throw-out bearings might go first, but might not. Just in case, it would be wisest to let the clutch out at stop signs. Is this so? ---
**Author:** ![hammos1](https://avatars.discourse-cdn.com/v4/letter/h/ba8739/32.png) [@hammos1](https://boards.straightdope.com/u/hammos1)\ **Post date:** [May 3, 2006, 10:48pm UTC](https://boards.straightdope.com/t/downshifiting-a-manual-automobile-to-slow-down/355170/49 "2006-05-03T22:48:49Z")
> [@Santos L Halper](#): > > That chart (the one in the upper right) Is anything but relatively constant. It’s divided up into eighteen segments. I guess it all depends what you mean by ‘relatively’. 😉 Looking at it again, I see the segment they claim for 140mph is visible. > [@Santos L Halper](#): > > I disagree. Yes, it’s long and straight but there are lots of cross streets, red lights to run and potential cross traffic to watch out for. The section right after that, along the Jardin des Tuileries until he turns through the Louvre is straight without cross streets and he gets up to a higher speed there. The section you mention (Quai des Tuileries) is even slower. The four fastest segments are: Avenue Foch (39 seconds to travel 0.84 miles- average speed 77mph) Avenue Champs Elysées (65 seconds to travel 1.3 miles- average speed 71mph) Quai des Tuileries (38 seconds for the 0.7 mile stretch- average speed 54mph) Avenue de l’Opéra (30 seconds to travel 0.45 miles- average speed 54mph) These are straight line speeds for the sections in question- they exclude the turns at the start and finish of each section, and some of the acceleration/ deceleration. As you say, for the rest of the trip he’s negotiating narrow streets, so we can exclude the possibility of 140mph here. The Avenue Foch stage is the fastest, and the midsection of this stage looks like the top speed. The absence of landmarks makes it difficult, but I think 85mph for a peak speed looks about right. There’s _no way_ he gets to 140mph during this ride- not even close. I have read elsewhere that Claude Lelouch has said recently that he himself did the driving in his Mercedes, which seems about right. The car being driven seems to have a top speed of 90mph or so, judging by its lack of acceleration beyond that. The sound is obviously dubbed as it does not correspond with the visuals. Incidentally, try watching it with the sound off- the effect is very different! The drive up Avenue de L’Opera in particular seems like a gentle stroll without the screaming engine and tyres. > [@Santos L Halper](#): > > Their calculations are just over seven miles and seven and a half minutes for an average of 56.5 mph, I would trust the figure I got from Google Earth more than theirs. For instance, they say “When he was nearing his destination, the Sacred Heart Basilica, he made a number of twists and turns down streets we could barely find on maps”. Pretty crappy maps then, if they can’t find Rue Norvins, Place du Tertre (one of the most famous squares in Paris) and Rue Azais. ---
**Author:** ![liberty](https://avatars.discourse-cdn.com/v4/letter/l/958977/32.png) [@liberty](https://boards.straightdope.com/u/liberty)\ **Post date:** [May 4, 2006, 1:38am UTC](https://boards.straightdope.com/t/downshifiting-a-manual-automobile-to-slow-down/355170/50 "2006-05-04T01:38:15Z")
Truck drivers downshift before heading down a mountain to use engine speed to help slow the truck down. ---
**Author:** ![js\_africanus](https://avatars.discourse-cdn.com/v4/letter/j/87869e/32.png) [@js\_africanus](https://boards.straightdope.com/u/js_africanus)\ **Post date:** [May 4, 2006, 2:38am UTC](https://boards.straightdope.com/t/downshifiting-a-manual-automobile-to-slow-down/355170/51 "2006-05-04T02:38:57Z")
> [@Santos L Halper](#): > > Yes, that’s about right. Cool. I tried it after work and it ain’t easy! On top of learning a new skill, I’ve old habits to break… Wish me luck. > [@](#): > > As for participating in a HPDE, I highly reccommend it. …I’ve known more than one person who started out attending one driving school and the next thing I knew they were spending every weekend autocrossing or seeing how much it’d cost them to pick up a dedicated track car. 🙂 I’ve heard of worse hobbies! 🙂 ---
**Author:** ![GusNSpot](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/gusnspot/32/436_2.png) [@GusNSpot](https://boards.straightdope.com/u/GusNSpot)\ **Post date:** [May 4, 2006, 4:29am UTC](https://boards.straightdope.com/t/downshifiting-a-manual-automobile-to-slow-down/355170/52 "2006-05-04T04:29:52Z")
Well, big rigs are going to automatic trannys now… Is nothing sacred? Used to be, you broke loose with the clutch and then never used the clutch again going up or down until you had to come to a complete stop. Didn’t grind no gears either… One time ( 1959 I seem to recall ) I drove me an old Diamond T ( or maybe it was a Reo ) with a 9 speed ‘road ranger’ over a 3 speed ‘Brownie’ with a 2 speed rear end. Least that was what he called them. I know I had 57 fwd combinations and 6 reverse. Some combinations were very nearly the same so you would use the easiest one to get to. ---
**Author:** ![Buck\_Rogers](https://avatars.discourse-cdn.com/v4/letter/b/958977/32.png) [@Buck\_Rogers](https://boards.straightdope.com/u/Buck_Rogers)\ **Post date:** [May 4, 2006, 5:56am UTC](https://boards.straightdope.com/t/downshifiting-a-manual-automobile-to-slow-down/355170/53 "2006-05-04T05:56:10Z")
Disk or drum braking is a reverse displacement of horsepower into heat to slow down the moving object. I know this from fact because I once designed a braking system for a moving shaft of high amounts of inertia. I specified using a westinghouse air brake on the spinning shaft and the specifications called for to size it by horsepower. I knew my horse power of the motor that drove the spinning shaft was 400 HP. I sized the brake according to that horsepower with an additional duty factor. Worked like a charm. Down shifting is using compression from the engine to slow down the moving object. What is better? Some measurables that come to mind to compare and evaluate slowing this moving object [vehicle] down are: 1. Cost of engine slowing vehicle down. 2. Cost of brake pads / rotors to slow down 3. Cost of clutch assemble to slow down 4. Safety 5. Enjoyment With all this being said I think one can plug and chug and make different decisions. I would think driving down a mountain item 1 and 4 would be more appropiate. Driving sports car on the open highway at high speeds I would think items 1, 3 and 5 would apply. Driving any car up to a light in traffic item 2 would apply. My point is different situations require different methods. ---
**Author:** ![commasense](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/commasense/32/3017_2.png) [@commasense](https://boards.straightdope.com/u/commasense)\ **Post date:** [May 4, 2006, 6:07am UTC](https://boards.straightdope.com/t/downshifiting-a-manual-automobile-to-slow-down/355170/54 "2006-05-04T06:07:13Z")
> [@js\_africanus](#): > > Okay, so my manual says shift up & down at 15mph, 25mph, 40mph, & 45mph. If I’m going fifity and need to brake, I apply my brakes. When the car slows to 45mph, I push down on the clutch; shift from fifth to fourth; and quick hit the accelerator with the side of my foot so that when I release the clutch in fourth gear, the rpm & speed properly match for that gear. Is that it? You’ve described the technique correctly, but in ordinary street driving, in a car with synchronizers, there’s no real reason to heel-toe downshift between consecutive gears, or to downshift through all the gears. On track (and conceivably on the street) heel-toe is used when you have to accomplish a large drop in speed, like at the end of a straight leading to a low-speed turn. You’re coming out of, say, fifth gear, and the corner calls for second gear, dropping from 130 mph to 40 in a couple of seconds. A lot of stuff is happening all at once, and if you were to let the clutch out in second gear just a little too early, you could over-rev the engine or cause rear wheelspin. This is far less likely to happen in a consecutive downshift because the gear ratios are closer, as is the car’s speed differential. So in a car with synchronizers, if you’re only going down one gear, just let the synchronizers do their job. On track I never bother to heel-toe unless I’m going down at least two gears, usually 5 → 2 or 4 → 2. [Here’s my home track, Summit Point Raceway.](http://www.comscc.org/tracks/images/summit-2.gif) I’ll heel-toe going into Turn One, coming down from about 130 to 45 or so, fifth gear to second. And again going into Turn Five, 100 → 30, fourth to second. Even in a car without synchronizers, a consecutive downshift doesn’t usually call for a throttle blip, even if you do have to double clutch. So I just don’t buy the argument that that’s what’s happening in the film. (I was going to look at it again, just to check, but the site is down at the moment.) I see no reason why a skilled driver would downshift in all the places we hear those engine blips. So IMHO it’s either one of the three things I postulated above, or the sound track was dubbed (or at least modified) after the filming. > [@](#): > > [hijack]—do you know if there are any HPDE opportunities in Michigan and what sort of prices can one generally expect to pay for a session? Thanks![/hijack] According to [Chasin’ Racin’](http://chasinracin.com/track-locator/states/mi.shtml), there are three tracks in Michigan: [GingerMan Raceway](http://chasinracin.com/track-locator/rtl_search.php?action=1&state=mi&trktag=gin), [Grattan Raceway Park](http://chasinracin.com/track-locator/rtl_search.php?action=1&state=mi&trktag=gra), and [Waterford Hills](http://www.waterfordhills.com/). Depending where you are in Michigan, you might also consider tracks in Ohio, Indiana, and Wisconsin. As I recommend in the other thread, go to the tracks’ Web sites, look for schools on their schedules, and contact the sponsoring organization. HPDE classes run from about $120 to $300 per day, plus hotel and incidental expenses. You’ll need a helmet. The school or the track may provide loaners, and for the first time that’s probably the way to go. Or you may be allowed to use a motorcycle helmet that you (or a friend) already own. But once you start doing HPDE regularly, you’ll want a real helmet of your own: a Snell SA 2005 rated helmet, which will run you at least $250. (SA=Special Application, intended for automobile racing, as opposed to motorcycle use. Some groups don’t allow motorcycle helmets.) But **Santos** is absolutely right: HPDE is very addictive. Watch out! ---
**Author:** ![js\_africanus](https://avatars.discourse-cdn.com/v4/letter/j/87869e/32.png) [@js\_africanus](https://boards.straightdope.com/u/js_africanus)\ **Post date:** [May 7, 2006, 2:59am UTC](https://boards.straightdope.com/t/downshifiting-a-manual-automobile-to-slow-down/355170/55 "2006-05-07T02:59:02Z")
> [@hammos1](#): > > The sound is obviously dubbed as it does not correspond with the visuals. Then it’s ironic how well the echoes match the varying confines of the environment. ---
**Author:** ![liberty](https://avatars.discourse-cdn.com/v4/letter/l/958977/32.png) [@liberty](https://boards.straightdope.com/u/liberty)\ **Post date:** [May 7, 2006, 4:28am UTC](https://boards.straightdope.com/t/downshifiting-a-manual-automobile-to-slow-down/355170/56 "2006-05-07T04:28:07Z")
> [@GusNSpot](#): > > Well, big rigs are going to automatic trannys now… Is nothing sacred? > > Used to be, you broke loose with the clutch and then never used the clutch again going up or down until you had to come to a complete stop. Didn’t grind no gears either… > > One time ( 1959 I seem to recall ) I drove me an old Diamond T ( or maybe it was a Reo ) with a 9 speed ‘road ranger’ over a 3 speed ‘Brownie’ with a 2 speed rear end. Least that was what he called them. I know I had 57 fwd combinations and 6 reverse. Some combinations were very nearly the same so you would use the easiest one to get to. Got one automatic gear on this tranny and it drives me nuts. Trucks need manual trannys, but several companies use all automatic trannys now. Of course, I’m not the best shifter. ---
**Author:** ![Mr.Slant](https://avatars.discourse-cdn.com/v4/letter/m/c57346/32.png) [@Mr.Slant](https://boards.straightdope.com/u/Mr.Slant)\ **Post date:** [May 7, 2006, 3:39pm UTC](https://boards.straightdope.com/t/downshifiting-a-manual-automobile-to-slow-down/355170/57 "2006-05-07T15:39:33Z")
> [@liberty](#): > > Got one automatic gear on this tranny and it drives me nuts. Trucks need manual trannys, but several companies use all automatic trannys now. Of course, I’m not the best shifter. Could you clarify? You are driving a car with a one-speed automatic transmission? A truck with a one-speed auto? ---
**Author:** ![EllisDee](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/ellisdee/32/4531_2.png) [@EllisDee](https://boards.straightdope.com/u/EllisDee)\ **Post date:** [May 7, 2006, 5:50pm UTC](https://boards.straightdope.com/t/downshifiting-a-manual-automobile-to-slow-down/355170/58 "2006-05-07T17:50:44Z")
> [@Airman Doors](#): > > [Here’s the movie](http://mirror.rtor.net/rendezvous20_04.mov), if you want to see it. I was holding my breath just watching it. My God. He almost clipped a pedestrian at one point. I lost count of how many red lights he ran. That was nuts. Awesome, but nuts. It was well worth the two hour download to see it. (Stupid dialup.) Holy shit! But in reading about it on the linked page, I noticed the other entry on that site, [The Run](http://hypertextbook.com/facts/2005/TheRun.shtml): > [@](#): > > Nissan’s promotional car film “The Run” is directed by two-time Academy Award winner John Bruno using fourteen different cameras. The film features a 350Z Track model accelerating through the streets of Prague in the Czech Republic. This six and a half minute film uses eight different camera angles to portray the elegance and speed of the “Z-car”, as they call it. Award-winning stunt driver Jimmy Roberts is the man behind the wheel. I want to download that in the worst way. Anybody got a link? ---
**Author:** ![spinky](https://avatars.discourse-cdn.com/v4/letter/s/59ef9b/32.png) [@spinky](https://boards.straightdope.com/u/spinky)\ **Post date:** [May 7, 2006, 6:52pm UTC](https://boards.straightdope.com/t/downshifiting-a-manual-automobile-to-slow-down/355170/59 "2006-05-07T18:52:04Z")
> [@Absolute](#): > > Here’s my understanding of what all the terms mean, and I’m pretty sure I’m right. I’m pretty sure you’re right too, although my execution of the singled-clutched, rev-matched downshift is subtly different: I blip the throttle while in neutral, rather than after jamming it in gear. This actually allows me to do it a little faster since the synchro has to do less work. It’s kind of like doing a double-clutched shift without letting the clutch out in the middle. I’m not very good at double-clutching, so I don’t do it regularly. Doing a bad job of double-clutching can cause as much clutch wear as not rev-matching at all (it’s generally done as quickly as possible by wannabe-racers, so mistakes in matching the revs are corrected violently at the expense of the clutch plate). ---
**Author:** ![commasense](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/commasense/32/3017_2.png) [@commasense](https://boards.straightdope.com/u/commasense)\ **Post date:** [May 7, 2006, 9:48pm UTC](https://boards.straightdope.com/t/downshifiting-a-manual-automobile-to-slow-down/355170/60 "2006-05-07T21:48:36Z")
> [@Ellis Dee](#): > > It was well worth the two hour download to see it. (Stupid dialup.) Holy shit! > > But in reading about it on the linked page, I noticed the other entry on that site, [The Run](http://hypertextbook.com/facts/2005/TheRun.shtml):I want to download that in the worst way. Anybody got a link? [Here’s a link](http://www2.uol.com.br/bestcars/carros/video/Nissan_350Z.mpg) to a “making of” video that includes some of the footage. It’s not the full version of “The Run,” though. But you can get the complete film on DVD [here](http://www.courtesyparts.com/Merchant2/merchant.mvc?Screen=PROD&Store_Code=CP&Product_Code=Z33-SPCL) for only $8.00. The DVD includes other stuff about how the film was made. Nissan sent me a copy of the disk when I ordered my 350Z back in 2002. My car is the same color and model as the one in the film. It’s pretty cool, but I had never seen the original on which it is based until this thread. (“The Run” concludes with the driver getting out to meet a girl, like the Lelouche film.) However, the 350Z version was done on closed off streets with permission. They only had time to run two or three full takes, and it reportedly cost millions to shoot. [Previous page](https://boards.straightdope.com/t/downshifiting-a-manual-automobile-to-slow-down/355170.md?page=2) [Next page](https://boards.straightdope.com/t/downshifiting-a-manual-automobile-to-slow-down/355170.md?page=4)