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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.
Who cares? I want my flying car!
karma capped
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
The evil monkey commands you to dance.
Well, here in the USA, we do use very heavy passengers:)
High-speed Road Trip (18.000KPH)
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.
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.
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.
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.
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.