The Bugatti Veyron

An anonymous reader writes "OK, most /.ers cannot afford the Veyron, but reading this article at HowStuffWorks is still fascinating. How do you fit 1,000 horsepower into a compact engine? How do you keep a passenger car on the road at 250+ MPH? The article links to a set of videos on the Veyron engine that are also very good. Are there any cars out there better than this?" There's also a story by Popular Science.

Comments

On the road?

[snake_dad]

How do you keep a passenger car on the road

Who cares? I want my flying car!

Re:On the road?

[FrYGuY101]

Then buy one!

Random fact...

[Chicane-UK]

Apparently the acceleratory (is that a word?) force of this car is so immense, that at full bore you are pulling the same kinds of G-Forces as you do on the vertical drops of a roller coaster ride.

Does 186MPH in 14 seconds.. must be a terrifying experience for both the driver, and for his wallet when he comes to fill it up! ;)

Re:Random fact...

[Bagheera]

I'm guessing you meant the G you feel at the -bottom- of the drop, which depends on the coaster, but I seem to remember is limited to under 2.5G for safety reasons. (I'm sure a coaster fan can confirm or correct this)

When you drop off the top, you get to accelerate at a little less than 1G (freefall minus any drag in the coaster), which, coincidentally, is about what it takes to make it to 60 MPH (~27M/sec) in 3 seconds.

So, in that regard you're more or less right.

Of course, the sad thing is that a decent sport bike can still beat it to 60, and some of them can give it a run for its money up to about 200.

Re:Random fact...

[Max von H.]

A good motorcycle like the latest Suzuki GSXR-1000 offers you the same acceleration (but not the same top speed), but much cheaper! It's a matter of power/weight ratio, therefore a bike which has a 180hp engine and weighs 170kgs like the 'zuki will have you cream your pants the same way ;)

It's not so terrifying, I assure you. Just... awesome!

Re:Random fact...

[UniverseIsADoughnut]

at 250 mph, that means he is traveling 4.17 miles in one minute, or about 4 times what you do in a normal minute when on a highway.

I come up with 3.13 mpg at 250 mph for the thing. Thats damn good.

But if he is crusing it won't take all that power, remember that fuel number was at full power. The driver would only be pulling full power with foot to the floor. A SUV may come with a 300hp engine to get it moving good, but it only needs ~18 hp to cruise at 55mph, and a car only needs ~15 hp to go 55. So most the time this car will be getting much better milage since like any vehicle it will only take ~15 hp for it to go highway speeds (if he goes that slow). so you could multiply his milage by 4-5 times. Also the car is very areodynamic, so it very well could do better then most cars out there.

Big powerfull engines only give you the potential to waste full, they do not cause the full usage. If you had 2 identical cars, but one has twice the HP they will both get the same mileage, but people being people many would get worse mileage with the more HP version since they would use it more and accel. faster. But for a driver who knows what they are doing they would get the same either way.

Still to say this thing sucks fuel based on peak power is not correct.

Oh and if you live in the US, gas is cheap, it's one of the cheapest substances on earth. Cheaper then milk, cheaper then water depending on how you purchase water, and gives you more of a return on your investment then damn near anything. Try going 30 miles (to and from any location) in a decent time frame for less then 2 bucks, only a car with a gallon of gas can do it that cheap.

Re:Random fact...

[theLOUDroom]

Apparently the acceleratory (is that a word?) force of this car is so immense, that at full bore you are pulling the same kinds of G-Forces as you do on the vertical drops of a roller coaster ride.

The actual G forces really aren't much more than you can accomplish in a typical street car, it's just that high horsepower cars are able to sustain 1G acceleration for much longer than your typical commuter car.

With the same tires, my car would probably stay neck and neck with this thing up to about 30 MPH, but then my ability to accelerate starts being limited by horsepower instead of tire traction.

This actually has the interesting implication that if you know the fastest you ever want to go and can sustain 1G acceleration up to that point, any additional horsepower is a waste of weight which will detract from the vehicle's braking and cornering performance. (Tire frictional force is nonlinear WRT weight.)

(Note: I'm ignoring downforce.)

Re:Random fact...

[AaronPSU79]

In a straight vertical drop you will be accelerating at G (9.8 m/s^2), and the g-force you will feel is zero (yes it may be slightly off due to wind resistance and such but you can assume zero). If this car can accelerate to 60 mph in 3 seconds its average horizontal g-force will be about 1G. So if we are traveling on a flat surface you will have 1G down (gravity), and 1G horizontal. Add the two together and you will end up with a max G of 1.4 at an angle of 45 degrees down from horizontal. In summary, accelerating in this car in a straight line your body will feel a max g of about 1.4, in a freefall vertical drop your body will feel 0G. So the poster was incorrect.

Re:Random fact...

[Danse]

That's ok. If you haven't lost the cops within 15 minutes, you're screwed anyway :)

Re:Random fact...

[JohnsonJohnson]

Big powerfull engines only give you the potential to waste full, they do not cause the full usage.

Correct.

If you had 2 identical cars, but one has twice the HP they will both get the same mileage,

Incorrect. Fuel consumption is based on a few variables, horsepower is not one of them. It is possible that two engines with widely different horespower ratings will have the same mileage performance but that's a matter of coincidence not science. As an example consider the highly efficient 100HP/liter powerplants in the S2000, 911 and M3 compared to the 5.7 liter (and that's a key number) powerplants of American muscle cars of a generation ago (Mustang, Camaro, Corvette etc.).

In general, mileage is a combination of compression ratio, engine size, gearing, torque curve, aerodynamic and mechanical (especially tire) efficiency, valve train mechanics and a host of other factors. Horsepower is simply not one of them.

but people being people many would get worse mileage with the more HP version since they would use it more and accel. faster.

Again, generally true

But for a driver who knows what they are doing they would get the same either way.

Again no, the largest factor in mileage these days is engine capacity. To run an engine you need to maintain stoichiometric balance of the fuel to air ratio, typically between 12 and 14 parts fuel to air by mass. The larger the engine capacity the worse the fuel efficiency at equivalent rpm and compreson ratios. Some manufacturers experimented with shutting down fuel flow to cylinders at cruise in order to make the engine effectively smaller. Emission problems due to accumulation of oil in deactivated cylinders, poor engine life due to thermal stress and pumping losses made that a failed technology. The next big thing in fuel efficiency for conventional piston engines is the variable timing and lift technology now available in BMW's 4.5liter V8 and soon to come form other manufacturers. Fully variable timing and lift allow optimization of pumping losses across the rev range, as well as improved combustion efficiency for higher torque at equivalent RPM, at the price of potentially larger valve train mechanical losses. Total power may also be limited by a lower RPM limit compared to other engines in the same class, although Formula 1 powerplants, which use a different but related valve control system, can apporach 20,000 rpm.

Still to say this thing sucks fuel based on peak power is not correct.

True, but the turbocharged (= high compression ratio at high rpm) 8! liter capacity of the engine doesn't help.

Re:Random fact...

[Matey-O]

Bzzt. You're _mostly_ right, but you've got a few critical things wrong.

Mileage is partially caused by the efficiency of the motor, and partly by the efficiency of the package it's wrapped in. my 89 Corvette could easily get 30-32mpg (or 3), my PT cruiser, with it's smaller motor attached to its more efficient manual tranny, gets 26-28 depending on A/C use.

My _98_ Corvette, while it has much less drag than the 89 - has a much more advanced motor but gets 4-6mph worse mileage. Why? because they weighted the variables towards performance, rather than mileage. it's also immune to heat soak, and has fewer parts, in light of the throttle by wire system removing ASR, Cruise, and throttle mechanicals.

Several manufaturers are releasing a displacement on command feature. making the V8 a V4 by shutting down four cylinders and removing the oil that keeps the lifters filled (and hence, lifting valves.) GM, Porsche and IIRC BMW have motors announced.

The next really REALLY cool tech you'll see is a camless motor. Lotus has done a LOT of research on solenoid actuated valves. If there's no cam, there's no limitation to valve timing! You can tune the motor to optimum fuel efficiency, max low end torque or max upper end hp.

Re:Random fact...

[JohnsonJohnson]

Bzzt. You're _mostly_ right, but you've got a few critical things wrong.

Fair enough, let's try it point by point because I'm feeling peevish.

Mileage is partially caused by the efficiency of the motor, and partly by the efficiency of the package it's wrapped in.

I believe I mentioned aerodynamic efficiency. Mechanical efficiency, like properly inflated tires, low rolling resistance tires (which is generally synonymous with low traction) and other effects also come into play. However I believe the message I was replying to was focused on the relationship of engine horsepower to mileage so I wanted to ignore packaging issues. Furthermore the original point was that horsepower cannot be used to infer mileage, but high horsepower does imply large engine displacement, holding the redline and compression ratio constant and allowing for similar engine material and component technology. Engine displacement is a large component of fuel efficiency and the Veyron's engine is huge in terms of displacement. There is simply no way (including caveats about red lines, compression etc.) to make an 8 liter engine as fuel efficient as a 3.5 liter engine.

My _98_ Corvette, while it has much less drag than the 89

I'd be surprised if that's really true, but I don't have anything at hand to answer that definitively. Suffice it to say though, Corvette's have generally gotten larger with each generation and whatever wind tunnel work has been done on the C5 may be offset by its increase frontal area with respect to the C4.

Several manufaturers are releasing a displacement on command feature. making the V8 a V4 by shutting down four cylinders and removing the oil that keeps the lifters filled (and hence, lifting valves.) GM, Porsche and IIRC BMW have motors announced.

Two nits to pick here: first of all what you are talking about is a variable number of active cylinders, a variable displacement engine actually changes the engine displacement without changing the number of active cylinders. Secondly, the idea of varying the number of active cylinders for efficiency is almost as old as the piston engine itself. No one has made one work reliably yet, so I'll consider it vaporware for now. For an idea as to how difficult this is to implement in practice, consider that we've got fully elctronically automated engines, hybrid powertrains and even Miller and Wankel designs all developed in the last 4 decades with no commercially produced variable active cylinder engines for automobiles yet.

The next really REALLY cool tech you'll see is a camless motor. Lotus has done a LOT of research on solenoid actuated valves.

While I appreciate the work of the wizards at Lotus as much as the next guy, this is more blue sky technology for the Popular Science "Aurora exists" crowd. Camless engines may become a regular production item someday, but at this point someday is no less than a decade or two away, just after they put the finishing touches on their fusion reactor. On the other hand, the existence of all these technologies makes GM's claim of producing a competitive fuel cell car by 2010 pretty silly. If you were working on technology that won't be productized for 10 or 20 years would you still do it if you knew it would be obsolete?

You can tune the motor to optimum fuel efficiency, max low end torque or max upper end hp.

Horsepower is torque times angular velocity, times a proportionality factor to take care of units. Thus max upper end HP is the same as max upper end torque. In general, current cam designs necessitate a trade off in the torque curve, although that is less the case with new engines, but that's a pecularity of the engineering not a fundamental difference between power and torque.

I don't even know why I wased my time writing this, like I said, just peevish I guess.

Audio

[lindec]

The Veyron is an interesting ride. It has one of the few W16 engines out there, not to mention quad turbos. One of the most amusing facts about the Veyron is the amount of effort that went into the sound system. Apparently, Bugatti demanded audio perfection, even when screaming along at 252 mph. I don't know if I speak for anyone else, but I think I 'd have larger concerns than the quality of my audio, if I was cruising at 252...

Automotive Vaporware

[eericson]

Anyone care to put money on this car making it to market?

The Bugatti Veyron is the last gasp of Piech's reign at VW (He had a thing for supercars and old nameplates). It's been plauged with reliablity issues and has cost VW a fortune to develop.

(Kinda sounds like Rhapsody a bit, doesn't it?)

-E2

Re:Automotive Vaporware

[Xzzy]

Eh, this is a bit of a peeve of mine. Hitler did NOT design the beetle. While Hitler was instrumental in getting the Volkswagen into production, he in fact did not create the beetle as those links would claim.

Ferdinand Porche had been designing automobiles for some 10 years when WWI ended, and as Germany's economy collapsed he realized the need for a family type car would be developing. For the next 15 years he pushed the idea, but at the time car makers were more interested in high-dollar luxury vehicles. It wasn't until 1934 he actually got a prototype built, an aircooled flat four-powered vehicle that almost anyone would recognize as a beetle. He had been working on the plans for several years prior.

In 1933/1934 Hitler came into power and started vocalizing his plans for the autobahn and the Volksauto. When Porche's employeer exited the automobile industry in that period, Porche basically panicked because he did not want his pet project to die. He did the letter writing campaign, and eventually Hitler heard about it. Through 1934 Porche and Hitler met, and found they both had similar views about building a "people's car". In the course of several meetings they settled on the specifications of what the car would be capable of.

From there Hitler funded Porche's prototyping and research.

There was a lot of simultaneous development going on here, Hitler had read much of Henry Ford's success, and was quite a car enthusiast. Hitler's idea of the volkswagen was his own, as much as it was Porche's own.

The design and engineering, however, is almost exclusively Porche's (though there are some allegations he stole some of the body design from another designer, I don't rightly remember who that would be though).

Later on, after WWII, the US saw the value of Volkswagen to rebuilding Germany's shattered economy, and put significant effort into rebuilding the destroyed factories and getting cars built again. In some ways, the US was as instrumental in VW's success as anyone else was.

W-16?

[CptKron]

A W-16 engine that can produce 1,001 horsepower

Every true rice boy knows anything more than four cylinders and a coffee can muffler is a waste.

Small engine, fast cars but what about airplanes?

[StateOfTheUnion]

Small engines fast cars. . . what about airplanes? Reminds me of a conversation with a friend that just bought the Mazda RX-8 (Wenkel Rotary Engine) . . . do cars push the envelope on internal combustion engines? or do airplanes?

60 years ago when internal combustion propellor planes were the standard, I'm guessing that the prop plane defined the hi-tech, high powered, low weight internal combustion engine. Anyone know if that's still true?

The question from the orginal conversation was "has anyone used a wenkel rotary (it has a low weight to power ratio) in a plane?" Why/Whynot . . .

Re:Ouch

[Anonymous Coward]

You have a French tank?

How...

[ottffssent]

How do you keep a passenger car on the road at 250+ MPH?

Well, here in the USA, we do use very heavy passengers:)

Not the most expensive

[Tyrdium]

How would you define the most amazing production car in the world? Would it be: * The car with the most horsepower? * The car with the fastest top speed and acceleration? * The most expensive car?

Sorry, but according to the Guinness Book of World Records, the most valuable car in the world is the Bugatti Type 41 Royale, at $15 million. It's also not the fastest overall, since it's beaten by racecars and the like.

Most horsepower?

[azav]

Carmack's Testarossa had 1198 bhp and they had trouble getting it dialed in and over 170. Pretty tractable though the wheels DID spin in 3rd gear when the turbos came up to speed at 85 mph.

Not sure if the Bugatti really does have "the most horsepower." Maybe most for a production car.

So obvious...

[Phexro]

"How do you keep a passenger car on the road at 250+ MPH?"

The answer for most people is: you don't.

Shop or compare prices

[Rob Parkhill]

I like how the HowStuffWorks article has a "Shop or Compare Prices" link at the very end.

It doesn't come up with too many matches, though.

its in their history.

[Brigadier]

Bugatti has been renowned not only as a sports car, but a luxury sports car. It's asking the question what is the absolute best I can buy. where in ferrari for exampe is primarily a sports car creature comforts only as needed. so given the history of the car this is not unheard off. On a side note engine technology has also been pushed as far as the marine world. if i'm not mistaken the original diesign for the W16 engine was taken from one developed for speed boats.

Re:its in their history.

[zeno_2]

"Similar to W12, W16 is made by mating two VR8s together, although at the moment Volkswagen group has not shown any VR8. The VR8 consists of 2 banks of 4-cylinder, mated at 15 deg. just like VR6. The two VR8s then join together at 72 deg.. In other words, W16 is just a W12 with one more cylinder added to each bank."

This was linked from here. Pretty interesting page for an amazing set of engines.

The thing about comparing cars and planes....

[Anonymous Coward]

Cars are designed to use their engine at 10% of peak output most of the time.

Planes are designed to use their engine at 90% of peak most of the time.

Better way

[Jozer99]

I can see a better way to get that much power. Make a redundant array of independant cars, or RAIC. Take 10 Kias, and weld them together. You get 1200 hp, plus better mileage. Also, who needs run flat tires, if it breaks down, pry one of the Kias out and drive to get help.

Extra Metal

[Anonymous Coward]

But wouldn't it have been easier to just add 398 lbs. of extra metal? Serious question. Is downforce from the spoiler(wing) that much better than extra metal?

Downforce has weight but not mass, so you don't need to expend horsepower accelerating it.

Re:250MPH?

[BeerSlurpy]

Tire grip increases with weight, but it is a log curve- the more you increase weight, the smaller the increases in traction are. Since each increase in weight also increases the mass, the tires have to do more work to change the direction of the car. Thus, heavy cars tend to develop less and less traction than lighter cars.

Adding downforce increases the car's "weight" for purposes of calculating the grip of the tires on the road, but doesnt increase the mass of the car that they have to change the direction of.

This is why the "ideal" race car is a stick figure formula 1 type car with a giant engine and huge wings. The downforce keeps the car stuck on the road with the force of many times its weight, but since the car is so light it can change direction with mind boggling speed. This is why formula one cars can develop over 5gs of sideways acceleration. The powerful engine helps to generate speed which in turn increases downforce. The cars actually grip more the faster they go.

HowStuffWorks is about to learn one more thing...

[TV-SET]

...and that is "How Slashdot works". :)

Re:Small engine, fast cars but what about airplane

[rcw-home]

60 years ago when internal combustion propellor planes were the standard, I'm guessing that the prop plane defined the hi-tech, high powered, low weight internal combustion engine. Anyone know if that's still true?

If you're referring to General Aviation propellor aircraft, the answer is definately no.

Chances are that the Lycoming or Continental engine in your average Cessna has changed very very little over the past 50 years. Even though intercooling and turbocharging are more common options today, they are still air-cooled, still cruise at 2500-3000rpm, and still magneto-fired. If you took a time machine, kidnapped an A&P from 1950 and put him here, he would probably die from the shock of everything being exactly the same. If not, he would begin a spree to kill all of the lawyers responsible.

By comparison, your car's engine is about 25% more fuel-efficient, can produce 50-100% more power per unit of displacement thanks to its higher speed, is liquid-cooled, is often variably-timed, will run on unleaded low-octane fuel, and is probably much quieter than an aircraft engine.

Many automotive engines, from Honda Goldwing engines to Chevy 350 cu. in. V8's and on up, are converted to air use in Experimental Aviation. They usually must be geared down to swing a decent-sized prop at a reasonable mach number (supersonic prop tips are bad). Some pilots do this because of the costs of a certified engine ($20k+, plus regular maintenance by an A&P), some do it because 100LL avgas is so expensive, some do it because they believe the end result will be more trustworthy.

As for rotaries, yes, they'll save you a bunch on weight (and size, if needed), and some people put them in experimental aircraft. They have very few moving parts which increases reliability. Unfortunately the combustion chamber in a rotary has so much more surface area (per unit of displacement) than the equivalent reciprocal engine that rotaries will probably continue to lag 15-20% behind reciprocal engines on fuel efficiency.

Most of the criticisms...

[ultramk]

...I'm reading here are kind of off-base.

"You can only drive 60(75,85)mph anyway, what a waste"

"The small-penised guys who buy this will kill themselves in 15 minutes"

"How pointless, it only gets 3mpg!"

etc, etc, etc.

Hmmmm, where do I begin. The people who are in the market to buy this automobile are not going to drive it every day. In fact, they will probably transport it in its own trailer if they take it to any concours, etc.

The main thing is, you're viewing this as a car. It isn't. It's a piece of kinetic, semi-functional sculpture. The collectors will buy this, then put it in their lovely 30,000sq.ft. showroom, and maybe take it around the block once in a while to get a little sun.

There are people with vast amounts of money who appreciate exceptional feats of engineering and design. Jay Leno is one. The Sultan of Brunai is another.

As far as the driving like assholes, that only happens with idiot rockstars and the like who just got a million dollar paycheck. The vast majority of the people driving this car will be doctors, investment bankers and the like. These guys drive carefully.

I live in Carmel, CA. We have the Concours d'Elegance here at Pebble Beach every year, and countless other similar events at nearby Laguna Seca. In addition, there are enough Ferraris and the like around here normally that I usually see 2-3 on the way to work every day. Hell, Porsches are common as VW beetles around here. I've never seen any of the more exotic cars driven less than super-carefully.

Yeah, it's a lot of money, but it costs much less then some of the jewelry worn at the Oscars... and this is much cooler then some bling-bling necklace.

-m

Re:Most of the criticisms...

[QuantumRiff]

First rule of driving in Southern California. On the highways, cut off the sports cars.. their breaks are better and their owners are more motivated to miss you! ;)

Article in error re: F1 cars

[JakiChan]

Just for the record, the article claims that F1 cars use a ground effect like the Bugatti. These days, actually, F1 has a few regulations to prevent that. The car bottom is flat and has a wood plank underneath that is 10mm +/- 1mm. If the plank is less than 9mm at the end of the race then the car is judged to have been riding too low.

See FIA 2004 Formula One Technical Regulations sections 13.2 and 13.3 for details.