Avoidable Contact #18: It’s actually rather easy being green; the case for front-wheel-drive.


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Story by Jack Baruth

Color me pleased; my 2009 Audi S5 has finally arrived, resplendent in vintage Porsche Lime Green. I hasten to add that this color is emphatically not the “Signal Green” which has become common on the current Porsche GT3 RS – it’s actually from Porsche’s 1973 and 1974 color book, and is a much brighter, more cheerful color than the rather more serious Signal Green. Readers of our S5 review may recall that I was smitten with Audi’s curvaceous V8-powered coupe from the moment I fired it up, so there was little doubt in my mind after our November test that I would eventually put one in my own garage. As with everything else in the Speed:Sport:Life “fleet”, from my Phaetons, to Zerin’s TT 3.2 Quattro, to the Big Dog’s Cayenne GTS, all the way to my sweetheart of a 993 pictured above, we had to pay for the car. We don’t get free “long-term testers” the way our friends in the print magazines or banner-ad-laden blogozines do. If we want a car for more than a week, we have to take out our wallets. It’s nice, in a way, because it means we’re putting our money where our mouths are. I liked the Audi S5, so I bought one. Simple as that. The other street (as opposed to race) car I bought this year, in case any of you care, was my mother’s 2008 Ford Focus SES sedan, another vehicle which received a generally positive review on these pages. So, as you can see, the manufacturers actually make money when they invite me to press events, because a bout 30% of the time I end up buying a car!

In the twenty-something days since I took delivery of the S5, pictures of the car have flown around the Internet with a rapidity usually reserved for lucky shots of Britney Spears making a bowlegged departure from Paris Hilton’s McMerc SLR. I’ve also received dozens of phone calls and text messages from friends and acquaintances who have spotted the Audi in traffic or parked somewhere. People who see the car in the metal seem to be about 70/30 in favor of my choice, while Internet users who see the car online (where, it has to be said, the color does not photograph quite “right”) are closer to 80/20 against. Some of the negative reactions are fascinating because their authors seem so… well, personally offended by the shiny S5. “I can’t believe Audi agreed to paint the car that color!” is a semi-common response. Well, they did agree, and they will also paint your new Audi in almost any color you like, thanks to their outstanding “Exclusive” program. The problem for most of these people is that they are afraid to own a German car in any color that is not silver, grey, or silver-grey, and the presence of brightly-colored German cars destroys their cherished Autobahn stereotypes. Of course, were they to ever sign off “World of Warcraft”, stumble blinking out into the afternoon light, borrow their parents’ Camrys, drive to the airport, and actually visit the hallowed Fatherland, they would see that the most common cars there aren’t silver Audis – they’re bright blue Lupos and yellow Renault Twingos. Germans like color, too.

Some of the younger Audi-forum readers are absolutely shocked that it’s possible to buy a car from Ingolstadt that isn’t utterly “tasteful” and “reserved”. How do I know that they’re young? It’s simple: they’re obviously too young to have ever seen the interior of a Seventies Audi, or even the seats of an ur-Quattro. The whole idea of “tasteful” German cars is a scam, kids. It was something the marketing people thought up twenty years ago so the dealers could stock a smaller selection of inventory. I grew up surrounded by lemon-yellow Mercedes diesels, brown Porsche 911SCs, pearl-white Audi 5000s, and baby blue big-bumper Bimmers, and believe it or not, none of the drivers of those cars ever died of color overdose. My father almost killed himself a few times pushing his orange Volvo off the freeway after it stalled for no particular reason, but I have no reason to believe that color was involved. Trust me on this one. I know that your local dealer has thirty-six BMWs on his lot and they are all either silver, grey, or black, but if you take out a BMW brochure and flip all the way to the back, past the endless photographs of optional skiing accessories but right before the disclaimer that tells you to obey posted speed limits, you will find little squares of color. While most of them are silver, grey, silver-grey, or black, chances are there will be a red or blue square on the page. It’s okay to go to the dealer, point to that square, and meekly inquire as to whether you might be permitted to purchase a car in that color. I’m not kidding. I even know a guy who bought an “arrest-me red” 740iL a few years ago… and they didn’t actually arrest him! Crazy, I know.

The other objection I’ve heard to my Audi purchase is a little more reasonable, at least on the surface. There are many variants to what my friends say, but it always boils down to something like this:

”As a racing driver, multiple Porsche owner, long-time car nut, and soi-disant automotive journalist, aren’t you smart enough to know that FWD-platform cars are, like, totally inferior to RWD-platform cars? Don’t you know that cars with overhanging front engines have lousy balance and will always understeer? Can’t you understand that something like a BMW M3 will always be a better drive than an Audi of any stripe? Have you noticed that pretty much everybody in the prestige-car business is moving to RWD? FWD sucks, even if you add a driveshaft to the rear wheels. I mean, don’t you read the Internet? Why would anybody bother with a front-wheel-drive car?”

It’s a fair series of questions. In an era when even Hyundai is pushing rear-wheel-drive as a selling point – a time when the Issigonis-inspired tranverse-engine layout has become inextricably associated with the very cheapest of cars – can there be any compelling reason to choose FWD? The answer is yes. I believe that FWD continues to be the best choice for a purely street-driven car, even if the driver of that car considers himself or herself to be a driving enthusiast. And since I don’t expect you to take that answer on faith, I’m willing to show you how, and why, FWD comes out on top in nearly every real-world driving situation… if, that is, you’re ready to listen. Are you?

To understand when, and why, FWD can be better, we have to start with how, and when, it is worse. In his book A Twist Of The Wrist, Keith Code explains the “dollar theory” of tire traction. Consider, if you will, that each tire has a fixed amount of traction available at any given time, and assign the value of one dollar to that traction. We can spend that entire dollar on cornering, as we would on a skidpad; we can spend the dollar on braking, as would be the case when doing perfect threshold braking before corner entry, or we can spend it on acceleration, as a skilled drag racer would when leaving the line. We can also split that dollar any way we like. When we brake and turn at the same time, we can spend fifty cents on braking and fifty cents on turn-in, or we can spend ninety cents on braking and ten on turn-in. What we cannot do is spend $1.05. When we ask for more than a dollar’s worth of combined traction from a tire, we’ll be “overdrawn” and the car will slide. Understeer is the condition you get when the front end is overdrawn; oversteer is when the rear end is using more than a dollar’s worth of traction per tire. Keith invented the dollar theory for motorcycles, but it holds true for cars as well. Ross Bentley tell us: “You can only use 100% of the available traction – and make sure you do.

The basic advantage of rear-wheel-drive is this: you can accelerate out of a corner earlier. Since you aren’t relying on the front wheels to both steer and accelerate, you can hit the gas sooner. There’s a secondary advantage – you can maintain corner speed slightly better because you can accelerate just enough to eliminate the braking effect of the turned front wheels without “overdrawing” the front tires – but at that point we’re into 10/10ths driving and serious racecraft, so we’ll forget about that for now. Earlier acceleration is what makes RWD the racer’s choice.

That’s the only dynamic advantage strictly linked to RWD, but there are two other disadvantages of traditional front-drivers which we should consider. It’s worth noting that these disadvantages also apply to all-wheel-drive cars which are based on traditional FWD layouts, such as Audi Quattros or SH-AWD Acuras. First, weight distribution. FWD cars tend to have more than fifty percent of the weight on the front wheels, and often the bulk of that weight is ahead of the front wheels. Having more weight on the front end needs you need more tire to control that weight, and most sanctioning bodies frown on having wider front tires. (Those of us who race FWD cars have all sorts of ways to make up for this, from arm-thick rear swaybars to crazy toe settings, which is why my Neon ends up naturally oversteering on corner entry. It’s not for the timid, trust me.) Pontiac is the only manufacturer in modern times to address this problem on a street car, offering a tire package for the V8-powered Grand Prix with slightly wider front tires, but customers tend to be actively repelled by the idea of having wide front tires. I’m not sure why, but there you go.

The second, and more important, dynamic disadvantage of a front-engine layout is polar moment of inertia. The more weight you can place at the center of the car, the quicker and easier it is to turn; think of a figure skater pulling her arms in during a spin and speeding up as a result. Placing weight at either end of a car affects its willingness to change direction, for the same reason that a heavy arrowhead makes an arrow fly true: the weight has effective “leverage” and is better able to resist sideways force. Rear-engined cars tend to have a slow-turn in, which is one of the three reasons why a typical 911 understeers on corner entry, (and someday we’ll discuss them all) but a front-engined car with big weight ahead of the front axle is even worse. It’s exactly like the arrow in our analogy. It wants to fly straight. Reluctance to turn is, of course, not a desirable condition in a race car, unless it’s a drag race car. The less polar moment of inertia – which is to say, the more weight you have at the center of the car, relatively speaking – the better, which is why all true race cars are mid-engined. It’s also why BMW makes such a big fuss about having most of the engine behind the front axle, and why Nissan is so fond of their so-called “front mid engine” layout. Getting the weight between the wheels reduces the inherent stability of the car, making it easier to turn.

You’ve heard all of this before, of course. You’re probably intimately familiar with all the reasons RWD is better. I’ve raced both FWD and RWD cars, and have experienced these advantages at the very limit myself. So why would anybody buy an FWD car, or a car with an overhanging front engine? The answer is simple: the reasons which argue against FWD for racecars actually support FWD in the real world.

Let’s start with The Dollar Theory. It still holds true in the real world, with one important caveat: it’s utterly irrelevant. On the street, we “performance drive” for our own enjoyment. There’s no clock against which to run, no competitor to outbrake you into the next turn. We’re looking for satisfaction, and that can be had just as easily in an FWD car. Some of the most satisfying canyon carvers in history have been FWD cars. The fellow who tells you that all FWD cars are “understeering pigs” is really telling you that he doesn’t understand how to trail brake. Furthermore, since we aren’t competing in a real race series with fixed rules, we can do anything we like. Are you dissatisfied with your Acura’s cornering ability? Get more tire. Want a faster corner exit in your MINI? Put a limited-slip diff in there. There are no sanctioning bodies to satisfy, so that minimal RWD corner-exit advantage is meaningless. We can make up for it in other ways.

What about weight balance? At low speeds, in low-traction conditions, FWD cars are better, because they have more weight on the wheels that accelerate, steer, and stop. There’s a reason BMW and Mercedes fit such wonderful traction-control systems to their RWD cars – they are necessary in many parts of the country. Under, say, forty miles per hour, FWD cars are better in the rain, better in the snow, better any time the condition of the road is in doubt. Racing drivers rarely find themselves driving up a slippery hill in the snow – but that’s a real-world condition that many of us experience every year. Of course, AWD cars are better still, but the funny thing is that Audis, Acuras, and other “natural FWD” cars are still better in the snow than AWD variants of “natural RWD” cars like Bimmers and Benzes, because they have that extra weight on the wheels that turn and stop.

We don’t all live in the snow belt, though, so what about high speeds? What about the freeway? Believe it or not, that’s where FWD really shines. Remember my analogy of the arrow with the heavy arrowhead? It’s hard to turn. It wants to fly straight. It’s stable – and that’s exactly what we want during freeway driving. To begin with, a stable car is inherently more restful for a long drive. I love my Boxster and 911, but over the course of a ten-or-twelve-hour drive, I do get a bit tired of the constant minor corrections needed to keep them pointed straight. When the camber of the road tilts, the Porsches want to follow it off onto the shoulder; when there’s a dip on the freeway, it unsettles them far more than it would a front-engined car. For long hauls, particularly at high speeds (like – gosh! – the Autobahn) you want a car which is stable by default.

”Sure,” you reply, “but what about emergency maneuvering?” Now we come to FWD’s finest hour. Most drivers steer too much in emergency freeway maneuvers. They unsettle the car beyond the point where they can control it. That’s why they spin, flip, or roll off the road. The perfect freeway car would be stable during the avoidance maneuver, and would naturally return to a straight-line balance when steering input was removed. Guess what kind of car does that best? Nope, it sure as hell isn’t a 911, or even a BMW M3. It’s the front-engined, FWD car that has the most predictable emergency handling and the quickest return to stability. This even benefits those of us who consider ourselves to be “skilled drivers” or “racing drivers”. We may be capable of steering a fast-moving Ferrari 430 around a crash… in daylight on dry pavement. Put us behind the wheel for six hours, get us tired, crank up the stereo, let our passengers start talking, put some rain on the road, take the light away… and pretty soon even a superhuman driver becomes merely human.

There are other popular objections to FWD, many of them centering around “refinement”, ride quality, and that sort of thing, but one drive in a Bentley Flying Spur, which is an FWD car under the skin, proves that most of those objections are pretty worthless. In the modern engineering era, it’s possible to make FWD-platform cars behave just as well as the RWD competition. If you doubt me, go test-drive a Lexus ES350 and IS350. Surprise! The FWD car rides better and feels more refined.

If FWD offers real-world safety, security, and comfort benefits, and I would contend that it certainly does, why are manufacturers in such a hurry to convert everything more “upmarket” than a Dodge Avenger to RWD? Why did Toyota and Hyundai expend such massive effort to make their flagship cars spin the back wheels? Why is GM endlessly flip-flopping between future plans for RWD or FWD Cadillacs?

As always in this industry, it’s a question of marketing. Front-wheel-drive is associated in the public mind with cheap, crappy little cars, while rear-wheel-drive is the land where BMW and Mercedes-Benz dwell. It’s about prestige, it’s about perception, it’s about that bloody Autobahn. It’s about journalists pretending to be racers, and racing journalists forgetting that, contrary to the advertisments, not every day is race day. It’s what Donald Fagen might call “The Royal Scam”, where we all pretend to see and feel things which don’t really exist. It sells magazines and generates clicks on banner ads, but there’s no substance behind the sizzle.

Even iconoclastic, wonderful Audi has finally fallen into the trap of being ashamed of FWD. I have been solemnly assured that the modern range of Quattro-drivetrain automobiles has “rear-biased” AWD, and that the new flip-flop differential arrangement has moved their engines slightly farther back in the car. They say it’s for sound engineering reasons, but I suspect it’s that old marketing mojo at work, trying to add some of that RWD-style frosting on a solid FWD cake. It doesn’t matter to me. The end, in this case, justifies the means. I’ll take my S5 just as it is, overhanging front engine and all. Color me pleased, indeed.

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Jack Baruth

47 CommentsLeave a comment

  • Points well taken on FWD advantages. Does FWD stability at high speed and pull traction help explain the lurid and long drifts that those crazy Arab guys do in Toyota Camrys and Honda Accords?

  • In the real world, FWD bias is the hands down winner for getting there in a hurry without stress. Those RWD posers ALWAYS get tired & drive off the performance FWD car’s pace in the real world.
    Enough said!

  • I never understood how something like green or orange can be considered more exciting than white or black. Colors are colors — to me, orange and white are simply two different choices. I didn’t buy a silver car because of some skewed perception of what people drive in the “motherland”. It looks good on the car, simple as that.

    ???

  • Here here on the color. I own a “fleet” of silver-gray cars, but that’s not really intentional; they were all used and I shopped on price. The world needs more orange cars in my opinion.

    Re: FWD Vs RWD in the real world.
    You missed one critical point in discussing driving for fun, rather than a timed race. I’d rather (intentionally or otherwise) “overdraft” my rear tires 9 times out of 10.

    Since we’re driving for fun and not in a race, I’m happy to leave any wet stop sign in a tail-wagging, counter-steering, driving-through-the-side-window RWD exhibition. Certainly more enjoyable than a wheel-hopping, torque-steering fwd attempt.

    That said, it would be nice if “real world” performance was more present in the current performance car dialog. I think we’d also quickly see that torque curves would be more useful and meaningful than peak HP.

  • First, if you felt the need to write this lengthy argument for your own car, I’d suspect that you also have doubts about its drive wheels.

    Second, when we’re buying a car for reasons besides practicality, we’re willing to overlook some real world disadvantages of the platform in order to get the “soul” we were really after. Your 993 tells me that you’re well aware of this. So, I would make the case that a RWD and/or midengine car typically satisfies our X-factor criteria, while FWD has none of that legendary “magic”. The counter to this statement may be, “but the S5 is the daily”. I’d probably then note the sticker price and question your commitment to the practicality that supposedly makes this car acceptable.

    Finally, the color is horrid. It might be more typical of me to fall head over heels for the heritage of that paint code, but on this car it just comes off crass. The final result is not unlike the balding geriatric in a fly yellow 355 Spyder; a billboard of the driver’s insecurity.

  • midshipman:

    Who’s worse, the guy who isn’t ashamed to be different, or the thousands of others who trumpet their individuality, then hide it in obscure e-code reflectors and tail lights that only their brethren will recognize?

    The final result is just a yuppy DINK in a new German luxury car, or a yuppy DINK wanna-be in a 15-year-old German luxury car.

  • Neither is worse. Individuality can be expressed as subtly or overtly as you want.

    What’s interesting is this strange need for people today to “express” themselves in everything they buy. From rainbow colored iPods to cheesy “skins” on mobile phones and computers.

  • well…no sideways fun for you I guess. I’d agree that in medium to medium-low speed turns there isn’t much of a difference between the two layouts, but in low speeds, especially on loose surfaces, a FWD car will definitely understeer and torque steer and a RWD car will provide you the option of a clean and smooth steering input start to finish. I’m sorry, but I drive a FWD car now, and I routinely grimace at torque steer and kick-back coming from my front end. I’ve also driven very good FWD’ers (integras, mini’s) and they are fun, but the problem isn’t resolved. I do not believe that 4wd cars fix this fault, they are better, but only once fully committed and/or sideways. by the way…I do know how to trail brake and I know when to apply throttle, the issue is really one of mechanical limitation.

  • Dr. Freu..err…midshipman: Sometimes a cigar is just a cigar. Why would you assume that any color choice that’s not pre-approved by your local salesdroid means that the owner “wants to be noticed”? Once upon a time when we had a bold and forward looking culture, brightly colored cars were commonplace, and hardly the cause of scandal. Even the “repressive” Victorian-era culture preferred brightly colored homes, carriages and clothing.

    Perhaps today’s cowering, foot-staring, cube-dwellers live in fear of being noticed for anything other than their sports team affiliation and odd sexual predilections, hence their affection for metallic dirt Camaccords.

    Then again, your psychosexual analysis may have some merit. Males in many animal species are brightly colored, both to show aggression and virility. Females and lesser males are often dull in color and take great pains to remain unnoticed. I’ll point out that during the past generation that the demographics surrounding car buying decisions has shifted drastically from nearly 100% male to predominantly female, and many of the remaining purchasing decisions are “mutual”.

    So, hen-pecked, wife-dominated beta males in bland cars everywhere thank you for your well-crafted defense of their mediocrity. ;)

  • Since I’ve opened a little discourse, it would only be right for me to stick out and play nice with everyone.

    It isn’t that I dislike brightly colored cars, or that I don’t believe expressing yourself via automobile is proper. In some cases, that sort of thing separates the merely interested from the connoisseur. I take every chance I can get to make that distinction in my own garage.

    It’s much more complicated than that. In my head, there’s an algorithm which takes into account driver demographic, car, and “flare” to reach a rough estimate of acceptability. Some drivers can get away with more flare, some cars suit certain drivers, and some cars better accept modification while still remaining tasteful.

    Here we have a middle-aged gentleman (I assume) in a high priced “classy” sedan, that is swathed in Notice Me Please Green. I insert the variables, take a look at my handy output chart, and I must conclude that this case closely resembles “Pimp in a Purple Cadillac”. Not good.

  • I thought this article was very well-written and well thought out. Unfortunately, I also disagree with almost every word. The way I see it, you make the following main points:

    1) A larger polar moment of inertia makes front-wheel-drive cars more comfortable on long journeys than rear-wheel-drives.
    2) Weight over the front wheels aids traction in the snow.
    3) A front-heavy car is more stable and less likely to spin during an accident-avoidance maneuver.
    4) Front-heavy cars ride better.

    These all make pretty good sense on the surface, particularly when compared to mid-engined vehicles (though I’d argue that mid-engined cars can be brilliant in snow) but I see a few problems when you remember that most rear-wheel-drive cars are still front-engined.

    To begin with, you point out that a front-wheel-drive car feels more stable on the highway. However, you only anecdotally compare this to mid- and rear-engined vehicles. In truth, a front-engine, rear-wheel-drive configuration generally has an even higher polar moment of inertia, and should therefore be even more stable and comfortable on highway drives. This is because the mass of the drive train is more spread out and pushed to both ends of the car.

    The next thing you bring up is that oft-repeated statement that front-wheel-drive cars are better in snow. I always took this old adage as truth until I began driving RWD vehicles through winter in Iowa. As it turns out, FWD cars are better than rear-drivers at only one thing: accelerating, usually in some random direction. I remember many times trying to drive some FWD car or another up a gentle hill with a slight sideways slope (most roads have one, to control rainwater). In that situation, whenever I pressed the accelerator to move forward, the car would ignore all steering inputs and immediately head for the curb. If I released the pedal to regain control, I’d start to slow down and wouldn’t make it up the hill. A RWD, on the other hand, with its uncanny ability to turn and accelerate at the same time, even in low-grip situations, would comfortably drive straight up the hill, if a bit sideways. Essentially, RWD allows you to both move and control your vehicle simultaneously, while FWD only allows one activity at a time. Although yes, the extra weight over the drive wheels means the RWD is easier to get stuck, I’d much prefer being safely stuck over losing control and crashing. I’ve also found occasional situations where my low-riding, front-heavy 2WD Ranger pickup got around much more easily than front-drive cars, because the front tires compacted loose snow before the drive wheels had to deal with it.

    You also talk about safety during an avoidance maneuver. Once again, you make a comparison to mid-engined exotica, and ignore the much more common and practical front-engine, rear-drive configuration. You also seem to confuse transitional behavior with steady-state behavior. It’s true, in a steady-state situation, FWD tends towards understeer while RWD tends towards oversteer. However, for safety reasons, manufacturers carefully tune suspensions so both configurations exhibit safe transitional understeer. The FWD layout, however, thanks to poor weight distribution and overworked front tires, has far more aggressive understeer behavior. What this means is that when you try to avoid an obstacle in a typical RWD, you will most likely avoid the obstacle completely and carry on your merry way. There is only a small chance of a spin, and I’d rather spin than crash, anyway. FWD, on the other hand, will understeer so badly that you’re likely to still hit the obstacle you were trying to avoid. The UK TV program Fifth Gear actually performed a test on this, using an Audi A4, BMW 3-series, and an Alfa Romeo 156. On a ‘greasy’ road, their driver had to swerve into the next lane and back in order to avoid two sudden obstacles. The rear-drive flew neatly through the course without any misbehavior. The AWD avoided the obstacles, but was plainly unsettled. The FWD understeered terribly and drove directly through an obstacle.

    Finally, you comment that a front-drive car rides better than a rear-drive car…by comparing a luxury-oriented FWD vehicle to a slightly sportier, more aggressive RWD vehicle. Of course the luxury car rides better – that’s the whole point of a luxury car. It’s all in the suspension tuning. Interestingly, the even weight distribution offered by RWD layouts should make suspension tuning much more straightforward, and provide overall more desirable results (whether those results are comfort or performance is up to the designer).

    The final complaint I have with your article is about fun. You never really talked about it, but it came to mind so I’ll comment anyway. I don’t really care how fast I go on the street (a task at which AWD is far superior to any 2WD technology anyway), but I do like to have fun. A large part of this is feeling like a part of the car – knowing what’s going on just by steering feel. It’s virtually impossible to have good steering feel when you’re running hundreds of horsepower through the wheels responsible for steering. Of course, this completely ignores torque-steer, which can be mitigated with equal-length half shafts, but can’t really be eliminated due to the complicated interaction of torque, steering, and suspension geometry.

    Again, you had a very interesting article. In fact, I think it would be faultless if you reworded a few things so it became an article called “in defense of front-engined cars,” because most of your arguments are valid complaints against mid-engined sports cars. I, however, firmly believe that front-wheel drive is inferior to rear-wheel drive in almost every way imaginable, save economy and packaging for passenger space.

    If you find the time to read my stupidly-long response, I’d love to hear from you! My email address should be attached to this post, but I’ll watch this comments section for a few days as well.

  • High Speed Driving Dynamics are more affected by suspension setup than anything. I drive a Mada3 Hatch 2.3L 5speed. I've modified the suspension with adjustable coilvers, front and rear swaybars, camber arms, etc. Needless to say, it rides harsh (however, it's fantastic for AutoX). Since rigidity has increased so much, it makes the car much less stable at high speeds, despite being front engined, fwd.

  • May I just say nice to read a relief to find anyone who really understands exactly what they are discussing on the web. You certainly find out how to bring an issue to light and make it important. More people should study it and understand this aspect of the story. I cant believe you are not very popular as you absolutely have the gift.

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