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User: mk2mark

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  1. Why are we hearing about this only now? on Volkswagen Concept Car Averages 262 MPG · · Score: 2

    This car is the third iteration of a concept car that has been around since 2009, this iteration since 2011. Is there some other significance that I am missing that puts it in the news today?

    http://en.wikipedia.org/wiki/Volkswagen_1-litre_car

  2. Re:Science works on Fear of Death Makes People Into Believers (of Science) · · Score: 1

    That's not true. I choose to believe what a scientist or a doctor tells me. The choice is important, as history teaches. It means more rigour in science, healthy skepticism and less people burning on stakes.

  3. Re:Short yellow lights are a safety hazard on Florida DOT Cuts Yellow Light Delay Ignoring Federal Guidelines, Citations Soar · · Score: 1

    Actually, the mass of the vehicle doesn't really significantly impact the stopping distance on reasonably level grade.

    See here.

    Actually it does. There's a vastly different co-efficient of friction between the road and a semi vs. a car. Tyre compounds, center of mass and probably the most significant difference being how well the suspension keeps the tyres in contact with the road. The heavier the "unsprung mass" (all the components between the dampers/springs and the road) the more intertia and the less quickly the suspension will keep the tyres in contact. Trucks have very heavy suspension in comparison to a car, making them worse at stopping.

  4. Re:There's nothing spectacular about the Rotary on Mazda Stops Production of the Last Rotary Engine Powered Car · · Score: 1

    I beg to differ, rotary engines are easily the best design of the non reciprocating pistons and I don't think you're being fair to them.

    Even if it was altogether true that they needed rebuilds that often it's still better than otto engines were doing at the same period in their development. Ditto for the fuel efficiency. While it is true that the higher output turbo engines can need rebuilds that often, I've heard of the naturally aspirated engines regularly running to 200-300k miles without a rebuild - and these motors still make around 100bhp/litre so they're reasonably stressed engines.

  5. Re:I got rid of spark plugs a different way entire on Lasers To Replace Sparkplugs In Engines? · · Score: 1

    You forgot about the chronic amounts of smug it puts out.

    Also unless you're my grandmother I think you mean 45mpg highway.

  6. Re:Golf Diesel on Mazda Claims 70 mpg For New Engine, No Hybrid Needed · · Score: 1

    I take offence to this. There are plenty of cars both in Europe and the States (and beyond) that are low powered by anyone's definition. The choice is there, and a reasonable statement is that a lower powered car will be cheaper. People can choose these cars if they wish. However, if they don't why does this amount to gross denial - and who are you to dictate someone's requirements to them? It's a perfectly valid argument that a more powerful car makes certain situations safer - this doesn't amount as you say to someone arguing that they can't drive on the freeway.

    Also a Euro is a unit of currency, when you call me one it conjures an image of a die-hard republican spouting about commies - except the polar opposite. Although no less ignorant.

  7. Re:How? on Cambered Tires Can Improve Fuel Economy · · Score: 1

    A certain amount of negative camber is actually beneficial in the situation you describe. As you hit the brakes, the front of the car squats, which compresses the suspension which changes it's geometry. Generally under compression, this geometry change results in positive camber, or the tyres tops pointing outwards. If the tyres were cambered negatively beforehand, under squat the tyres approach a parallel state with the road below (assuming it's level).

    Designing suspension geometry is an exercise in compromise. The question here is do you want your tyres parallel with the road under compression or not. Since under compression you're generally in a situation where you're testing the tyre's grip, it seems to me that a degree or 2 of negative camber is actually ideal.

  8. Re:you can teach this stuff to them... on Louisiana, Intelligent Design, and Science Classes · · Score: 1

    Just for the record there's a case for dinosaurs in the bible. Read the end of Job where he talks about the Behemoth and the Leviathan, or note the numerous mentions of "dragons"/taninim.

    Your Sunday school teacher might have been full of crap, don't be fooled by the myopic views of others.

  9. Re:In other news today... on George Lucas C&Ds 'Lightsaber Laser' · · Score: 1

    What about something less mainstream? I heard there was some dude called John Delorean who had a brief foray into building sports cars in Ireland during the 80's - surely something this obscure would fit the bill?

  10. Re:GM on Avoiding GM Foods? Monsanto Says You're Overly Fussy · · Score: 1

    How exactly do you know one end of a football from another?

  11. Re:Please, electrical gods, make it 12V on Working Toward a Universal Power Brick For Laptops · · Score: 1

    Also, unless the car is turned off the voltage regulators on car alternators mean you're getting closer to 14v

  12. Re:Absolutely not. on ARM Exec Says 90% of PC Market Could Be Netbooks · · Score: 1

    Even Intel's Atom processor is essentially an overclocked 486.

    How do you figure? 1m vs 45nm, 40 MIPS vs 3300 and vastly different instruction sets?

  13. Re:Innovation! on The Last GM Big-Block V-8 Rolls Off the Line · · Score: 1
    Who on earth modded this informative????

    A V allows you package more displacement in to smaller overall volume or to have less car to package around given in engine. Weight savings from a V engine boosts handling performance and economy. Yet an inline engine will be cheaper than a V, due to one, block, single manifolds, two camshafts instead of four.

    Since a v engine has twice as many heads how can it possibly weigh less or have more displacement for it's size?

    V engines don't have the length of an inline engine, and are more cube shaped which tends to suit application to more engine bays.

    Difference in power may come from firing order, and the path intake charge and exhaust gas take and a small reduction in friction in a Inline 4 or 6. Inline 6s can have a good cross flow set up for top end power when mounted longitudnally in a front engined car (short straight intake runners and 6 into 1 headers, make a good turbo platform. BMW, Nissan and Toyota have exploited this to great effect in racing and in road cars. Aftermarket Nissan Skyline motors with 6-1 turbo manifolds make whopping power.

    I don't think I've ever seen a non-cross-flow v-engine. They're at least as suited to a cross-flow head as an inline engine.

    Turbo engines are "suited" to 6-1 manifolds because there's very little advantage in tuning the exhaust of a turbo'd engine. The 6-1 manifold is chosen because of this and because it takes up less space. If pulse tuning was any use on a turbo engine, they'd all be 6-2-1 as in an n/a application you could tune the engine to produce torque as the turbo spools.

    I'd also wager that Skylines make whopping power because of the "whopping" turbo.

    In the end, V8s rose to greatnews because it was probably the best balance between a number of cylinders, dimensions, displacement etc. A four cylinder block is about as long as you want to go. Big displacement engines need a greater number of pistons to stop the piston speeds getting out of hand along with smoothness reasons. Eight cylinders is just right, for big power or a big engine.

    Nonsense, you can counteract piston bore with the stroke of the engine to have whatever speed you wish. Eight cylinders were chosen probably more because this leads to a more suitable ratio between engine dimensions.

    A inline 6, and a 90 degree V12 and a boxer six are probably the three ideal engines, having perfect balance. The greatest engine of them all on the balance of all considerations, including, cost, complexity and packaging is the inline four. That's why V8s are made out of two of them:

    Wrong again. An inline 6 has primary and secondary harmonic balance - about as good as any engine could hope to have, but not perfect. A boxer 6 does not have this, usually a boxer is chosen for a low centre of gravity/space saving to slap a bunch of turbos on top. A v12 has the same balance as an inline 6 no matter what the angle is, 90 or otherwise. It's a little smoother because of the increase in fires per revolition.

    American V8s most often really are just two inline four engines stuck together. Right down to the split-plane (cross-plane) crankshaft. Yes there are hack mechanics who have lopped off one bank of cylinders to make a inline four, it works. Unfortunatley cross-plane crankshafts have a lot of drawbacks including difficult to control vibration, unbalanced piston movement, poorer exhaust scavanging in certain exhaust configuartions and need for counterweights that add rotational inertia. Yes every American V8 you drove had a dirty kludge under the hood.

    Inline 4's invariably have flat-plane cranks, so you've got that backwards too. Crossplane crank v8's have secondary balance, which actually means they're better balanced than flatplanes - Maybe you heard that flatplane's rev higher so thought this may be the reason they're better balanced? Not so, the rea

  14. Re:Of course, there is another solution on Vatican Debates Possibility of Alien Life · · Score: 1

    Speaking as a christian, I absolutely agree with this point of view. I'm not going to disagree that my views are blatantly unscientific and radical, however I will disagree that I may be wrong. I don't say this to be confrontational, condescending or brash, the only reason I say it is to show the distinction (in my reasoning) between my scientific and religious views.

    I wouldn't view myself as an unreasonable person, but events in my life and a very real relationship leave me in no doubt that what I believe is true - absolutely true. It's not scientific, but it's logical (to me at least).

  15. Re:PR on Scientists Decry "Horrifying" UK Border Test Plan · · Score: 1
    54% + 40% + 9% + 3% = 106% not to mention the fact that Hispania is a part of Europe.

    We seem to be doing just fine.

    Sure you do!

  16. Re:What about Qwantz? on xkcd To Be Released In Book Form · · Score: 1
  17. Re:In real units... on Bugatti's Latest Veyron, Most Ridiculous Car on the Planet? · · Score: 1

    But can it run Vista?

  18. Re:Nothing wrong with his analogy on CoS Bigwig Likens Wikipedia Ban to Nazis' Yellow Star Decree · · Score: 1

    That was an awesome analogy.

  19. Re:I'm a bit skeptical... on The Great Ethanol Scam · · Score: 1

    1. Your 40 - 60% number is way off.

    2. If your engine has a knock sensor (anything remotely modern), your ECU should be able to change the timing to take advantage of the higher octane and better burn characteristics the ethanol gives the fuel, which in some cases can even increase economy, while at the same time giving you a boost in performance. This is especially the case for turbo engines.

  20. Re:Don't blame me, on The Great Ethanol Scam · · Score: 1

    I'd class myself as a motorhead and I'm totally in favour of ethanol. Sure it's less calorific than petrol, but it's vastly higher octane, and it burns a lot cooler and more completely. Basically meaning that if you run a higher compression engine (which you can because of the octane rating) then you can close the gap on the petrol advantage.

    Another result of the better burn is far fewer emissions, which petrol engines need to be tuned for. I'm not sure on the numbers, but what if you didn't need the power/economy sapping catalytic converter anymore?

    It does however, have to be neat ethanol to take full advantage. The flex fuel cars are hampered by the petrol component, but if Brazil can do it then why not everyone else?

  21. Re:Is it safe? on Segway, GM Partner On Two-Wheeled Electric Car · · Score: 1

    Those pesky buses, always trying to clip people!

  22. Re:If Windows 7 is as fast as they claim on XP Reprieve, Downgrade May Continue After Win7 · · Score: 1

    That might be a valid point if the only thing that mattered was speed. Windows 95/3.1/DOS might be faster, but I don't know how you could argue against the fact that all of them would be vastly unsuitable for the bulk of what people do on PC's these days.

    You might be right in what you say, but you'd also be right in saying the sky is blue. Either way you'd be contributing about the same amount to what's being discussed.

  23. Re:Linus Pauling on The Global Warming Heretic · · Score: 1

    My Father is a civil engineer by trade, his only programming experience was a small amount of pascal in college. However during my own college degree in programming I was pretty astounded at the insight he had into what I was doing based on the small overview of things I gave him. He wasn't able to deal with specific syntax but he could clearly see what was happening on a conceptual level - sometimes even to the point where he could assist. Frustratingly, I particularly found this happened after extended stints of fighting with language specifics - he tended to pop up at the end of said stints and say "why didn't you do it this way", proceeding to point out something that tended to be a lot simpler than what I was doing.

    I'm not really trying to make a larger point with regard to this topic, but sometimes people _can_ just be intelligent and insightful enough to the point of indeed being able to even see the overall picture better than someone one who spends their time doing it.

  24. Down to a fricken T on Apple Touch-Screen Netbook? · · Score: 1

    An anonymous source in Taiwan? http://www.misterbg.org/AppleProductCycle/

  25. Re:Pied Piper on How To Keep Rats From Eating My Cables? · · Score: 1

    Genius! Instead of removing the mice from the situation, you remove your pipe-playing-fancydress-self to the local rodent-free mental institute!