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#31
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Europe Considers BAN ON SPORTS CARS to Combat Global Warming
Alan Baker wrote:
> > In article >, > Greg Procter > wrote: > > > "Fred G. Mackey" wrote: > > > > > > Marc Gerges wrote: > > > > Sandy > wrote: > > > > > > > >>"Marc Gerges" > wrote in message > > > ... > > > >> > > > >>>There's no benefit in driving faster than 80-90 mph in my eyes. > > > >>> > > > >> > > > >>The benefit is that you get where you're going sooner. Duh. > > > >> > > > > > > > > > > > > Yes - in theory. In practice at most times on most roads I drive there's > > > > enough traffic and other reason to reduce your speed that in the end you > > > > won't spend a lot of time at 100+ mph and therefore your time saving is > > > > relatively minor. You will spend a lot of time accelerating to this kind > > > > of speed and that is expensive in gas. > > > > > > > > Real world numbers I pushed a car capable of 140mph on german highways > > > > for a trip of about 3 hours and won about 15 minutes. Cost a lot of > > > > stress and a fill up (which cost those fifteen minutes). Not worth it > > > > for me. Maybe different on other roads and conditions. > > > > > > so you think you wouldn't have had to fill up if you only went 90? > > > > Assuming a car engine that is as efficient at 140 as 90, it is going to > > use 2.4 times as much fuel at 140. > > Let's look at a specific case: > > My Miata gets about 500km on a tank at 100 kph. So each 500 km would > involve one fuel stop of -- counting getting off the highway, fueling up > and getting back to speed -- ten minutes. That reduces my average speed > to 500/(5 + 1/6) kph. > > In fact, you can generalize to: > > e: fuel economy in kilometres per litre. > > t: tank capacity in litres > > s: speed in kilometre per hour > > f: fueling time in hours > > V: average speed. > > V = et/(et/s + f) > > Which in this instance equals 96.8 kph. > > Now, if we raise the speed to 120 kph, we know that power (and thus > roughly fuel flow per unit time) will rise with the square of that > increase, but distance travelled will also rise in proportion, so fuel > economy will fall in inverse proportion to the increase in speed > (approximately)[1]. So at 1.2 times the speed, my Miata should get > something like 416.7km on a fill. > > Plugging that figure into our equation... > > V = 416.7(416.7/120 + 1/6) = 114.5kph > > So how about 160kph (getting close to as fast as my Miata can go): > > 500/(160/100) = 312.5 kilometres on a tank and > > V = 147.42 kph. > > What about 200kph? > > 250 kilometres on a tank and V = 250/(250/200 + 1/6) = 176.5kph. > > Still faster point to point. > > How about 400 kph? Insane, I know, but this is all somewhat hypothetical. > > 125 kilometres per fill and an average speed of 260.9 kph. > > Now, what if we *double* the fill time? > > 100kph now gives 93.75kph average. > > 120kph gives 109.5 > > 160 gives 136.7 > > 200: 157.9 > > 400: 193.54 > > So, as long as you don't mind paying the cost, don't worry about the > argument that you shouldn't drive faster because it will end up taking > you longer because of the time you lose filling up. > > [1] This webpage shows that my linear relationship between speed and > fuel economy isn't far off. If anything it shows that the relationship > actually favours faster speeds: > > <http://www.recumbents.com/wisil/demma/superMileageVehicle.htm> That would work on straight unrestricted roads, but where does one find one of those??? Start adding bends with (say 80km/hr) restrictions and all your examples have to brake and accelerate back to cruising speed - gurgle gurgle gurgle ;-) Around here, if I drive at 100km/hr I just catch up to the next block of cars travelling at 70-95km/hr. Regards, Greg.P. |
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#32
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Europe Considers BAN ON SPORTS CARS to Combat Global Warming
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#33
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Europe Considers BAN ON SPORTS CARS to Combat Global Warming
In article >,
Greg Procter > wrote: > Alan Baker wrote: > > > > In article >, > > Greg Procter > wrote: > > > > > "Fred G. Mackey" wrote: > > > > > > > > Marc Gerges wrote: > > > > > Sandy > wrote: > > > > > > > > > >>"Marc Gerges" > wrote in message > > > > ... > > > > >> > > > > >>>There's no benefit in driving faster than 80-90 mph in my eyes. > > > > >>> > > > > >> > > > > >>The benefit is that you get where you're going sooner. Duh. > > > > >> > > > > > > > > > > > > > > > Yes - in theory. In practice at most times on most roads I drive > > > > > there's > > > > > enough traffic and other reason to reduce your speed that in the end > > > > > you > > > > > won't spend a lot of time at 100+ mph and therefore your time saving > > > > > is > > > > > relatively minor. You will spend a lot of time accelerating to this > > > > > kind > > > > > of speed and that is expensive in gas. > > > > > > > > > > Real world numbers I pushed a car capable of 140mph on german > > > > > highways > > > > > for a trip of about 3 hours and won about 15 minutes. Cost a lot of > > > > > stress and a fill up (which cost those fifteen minutes). Not worth it > > > > > for me. Maybe different on other roads and conditions. > > > > > > > > so you think you wouldn't have had to fill up if you only went 90? > > > > > > Assuming a car engine that is as efficient at 140 as 90, it is going to > > > use 2.4 times as much fuel at 140. > > > > Let's look at a specific case: > > > > My Miata gets about 500km on a tank at 100 kph. So each 500 km would > > involve one fuel stop of -- counting getting off the highway, fueling up > > and getting back to speed -- ten minutes. That reduces my average speed > > to 500/(5 + 1/6) kph. > > > > In fact, you can generalize to: > > > > e: fuel economy in kilometres per litre. > > > > t: tank capacity in litres > > > > s: speed in kilometre per hour > > > > f: fueling time in hours > > > > V: average speed. > > > > V = et/(et/s + f) > > > > Which in this instance equals 96.8 kph. > > > > Now, if we raise the speed to 120 kph, we know that power (and thus > > roughly fuel flow per unit time) will rise with the square of that > > increase, but distance travelled will also rise in proportion, so fuel > > economy will fall in inverse proportion to the increase in speed > > (approximately)[1]. So at 1.2 times the speed, my Miata should get > > something like 416.7km on a fill. > > > > Plugging that figure into our equation... > > > > V = 416.7(416.7/120 + 1/6) = 114.5kph > > > > So how about 160kph (getting close to as fast as my Miata can go): > > > > 500/(160/100) = 312.5 kilometres on a tank and > > > > V = 147.42 kph. > > > > What about 200kph? > > > > 250 kilometres on a tank and V = 250/(250/200 + 1/6) = 176.5kph. > > > > Still faster point to point. > > > > How about 400 kph? Insane, I know, but this is all somewhat hypothetical. > > > > 125 kilometres per fill and an average speed of 260.9 kph. > > > > Now, what if we *double* the fill time? > > > > 100kph now gives 93.75kph average. > > > > 120kph gives 109.5 > > > > 160 gives 136.7 > > > > 200: 157.9 > > > > 400: 193.54 > > > > So, as long as you don't mind paying the cost, don't worry about the > > argument that you shouldn't drive faster because it will end up taking > > you longer because of the time you lose filling up. > > > > [1] This webpage shows that my linear relationship between speed and > > fuel economy isn't far off. If anything it shows that the relationship > > actually favours faster speeds: > > > > <http://www.recumbents.com/wisil/demma/superMileageVehicle.htm> > > That would work on straight unrestricted roads, but where does one find > one of those??? > Start adding bends with (say 80km/hr) restrictions and all your examples > have to brake and accelerate back to cruising speed - gurgle gurgle > gurgle ;-) Around here, if I drive at 100km/hr I just catch up to the > next block of cars travelling at 70-95km/hr. There are lots of places where you can cruise along a highway at significantly above the speed limit and never need to brake. Even where you *do* need to brake, it isn't going to change the basic premise. -- Alan Baker Vancouver, British Columbia "If you raise the ceiling four feet, move the fireplace from that wall to that wall, you'll still only get the full stereophonic effect if you sit in the bottom of that cupboard." |
#34
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Europe Considers BAN ON SPORTS CARS to Combat Global Warming
Alan Baker wrote:
> > In article >, > Greg Procter > wrote: > > > Alan Baker wrote: > > > > > > In article >, > > > Greg Procter > wrote: > > > > > > > "Fred G. Mackey" wrote: > > > > > > > > > > Marc Gerges wrote: > > > > > > Sandy > wrote: > > > > > > > > > > > >>"Marc Gerges" > wrote in message > > > > > ... > > > > > >> > > > > > >>>There's no benefit in driving faster than 80-90 mph in my eyes. > > > > > >>> > > > > > >> > > > > > >>The benefit is that you get where you're going sooner. Duh. > > > > > >> > > > > > > > > > > > > > > > > > > Yes - in theory. In practice at most times on most roads I drive > > > > > > there's > > > > > > enough traffic and other reason to reduce your speed that in the end > > > > > > you > > > > > > won't spend a lot of time at 100+ mph and therefore your time saving > > > > > > is > > > > > > relatively minor. You will spend a lot of time accelerating to this > > > > > > kind > > > > > > of speed and that is expensive in gas. > > > > > > > > > > > > Real world numbers I pushed a car capable of 140mph on german > > > > > > highways > > > > > > for a trip of about 3 hours and won about 15 minutes. Cost a lot of > > > > > > stress and a fill up (which cost those fifteen minutes). Not worth it > > > > > > for me. Maybe different on other roads and conditions. > > > > > > > > > > so you think you wouldn't have had to fill up if you only went 90? > > > > > > > > Assuming a car engine that is as efficient at 140 as 90, it is going to > > > > use 2.4 times as much fuel at 140. > > > > > > Let's look at a specific case: > > > > > > My Miata gets about 500km on a tank at 100 kph. So each 500 km would > > > involve one fuel stop of -- counting getting off the highway, fueling up > > > and getting back to speed -- ten minutes. That reduces my average speed > > > to 500/(5 + 1/6) kph. > > > > > > In fact, you can generalize to: > > > > > > e: fuel economy in kilometres per litre. > > > > > > t: tank capacity in litres > > > > > > s: speed in kilometre per hour > > > > > > f: fueling time in hours > > > > > > V: average speed. > > > > > > V = et/(et/s + f) > > > > > > Which in this instance equals 96.8 kph. > > > > > > Now, if we raise the speed to 120 kph, we know that power (and thus > > > roughly fuel flow per unit time) will rise with the square of that > > > increase, but distance travelled will also rise in proportion, so fuel > > > economy will fall in inverse proportion to the increase in speed > > > (approximately)[1]. So at 1.2 times the speed, my Miata should get > > > something like 416.7km on a fill. > > > > > > Plugging that figure into our equation... > > > > > > V = 416.7(416.7/120 + 1/6) = 114.5kph > > > > > > So how about 160kph (getting close to as fast as my Miata can go): > > > > > > 500/(160/100) = 312.5 kilometres on a tank and > > > > > > V = 147.42 kph. > > > > > > What about 200kph? > > > > > > 250 kilometres on a tank and V = 250/(250/200 + 1/6) = 176.5kph. > > > > > > Still faster point to point. > > > > > > How about 400 kph? Insane, I know, but this is all somewhat hypothetical. > > > > > > 125 kilometres per fill and an average speed of 260.9 kph. > > > > > > Now, what if we *double* the fill time? > > > > > > 100kph now gives 93.75kph average. > > > > > > 120kph gives 109.5 > > > > > > 160 gives 136.7 > > > > > > 200: 157.9 > > > > > > 400: 193.54 > > > > > > So, as long as you don't mind paying the cost, don't worry about the > > > argument that you shouldn't drive faster because it will end up taking > > > you longer because of the time you lose filling up. > > > > > > [1] This webpage shows that my linear relationship between speed and > > > fuel economy isn't far off. If anything it shows that the relationship > > > actually favours faster speeds: > > > > > > <http://www.recumbents.com/wisil/demma/superMileageVehicle.htm> > > > > That would work on straight unrestricted roads, but where does one find > > one of those??? > > Start adding bends with (say 80km/hr) restrictions and all your examples > > have to brake and accelerate back to cruising speed - gurgle gurgle > > gurgle ;-) Around here, if I drive at 100km/hr I just catch up to the > > next block of cars travelling at 70-95km/hr. > > There are lots of places where you can cruise along a highway at > significantly above the speed limit and never need to brake. It's not advisable in NZ, between hidden speed cameras and numerous police patrols. Each 10km above gets a fine, 130km looses your licence. :-( > > Even where you *do* need to brake, it isn't going to change the basic > premise. Acceleration uses a lot of fuel. > > -- > Alan Baker > Vancouver, British Columbia > "If you raise the ceiling four feet, move the fireplace from that wall > to that wall, you'll still only get the full stereophonic effect if you > sit in the bottom of that cupboard." |
#35
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Europe Considers BAN ON SPORTS CARS to Combat Global Warming
necromancer > wrote in
th.net: > Nate Nagel: >> necromancer wrote: >> > MLOM: >> > >> > << reply limited to r.a.d >> >> > >> >>On Jul 13, 6:00 am, "Murderous Speeding Drunken Distracted Driver >> >>(Hector Goldstein)" > wrote: >> >> >> >>>noone wrote: >> >>> >> >>> >> >>>>I'm all for it if we can ban pickups and SUVs in the process. >> >>> >> >>>I'm thinking most americans drivers that I've witnessed should go >> >>>back to horse and buggy. >> >>> Man, I HATE responding to this irrational thing. But... If you can't handle driving a car, you'll be even more dangerous driving a horse & buggy. Takes even more skill & knowledge. Doug |
#36
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Europe Considers BAN ON SPORTS CARS to Combat Global Warming
Marc Gerges wrote:
> Fred G. Mackey > wrote: > >>>Real world numbers I pushed a car capable of 140mph on german highways >>>for a trip of about 3 hours and won about 15 minutes. Cost a lot of >>>stress and a fill up (which cost those fifteen minutes). Not worth it >>>for me. Maybe different on other roads and conditions. >> >>so you think you wouldn't have had to fill up if you only went 90? > > > Rising speed decreases mileage. Very quick. > I'm not disputing that even though I have to endure your poor grasp of the English language. Driving at 90 for more than 3 hours is likely going to cause most drivers to have to stop for gas. > You don't notice really when you spend only a minute or two 'up there'. > Once you're at >>100 mph for an hour, you'll notice how quickly the gas > gauge starts to drop. > > cu > .\\arc |
#37
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Europe Considers BAN ON SPORTS CARS to Combat Global Warming
In article >,
Greg Procter > wrote: > > > > > > >>>There's no benefit in driving faster than 80-90 mph in my eyes. > > > > > > >>> > > > > > > >> > > > > > > >>The benefit is that you get where you're going sooner. Duh. > > > > > > >> > > > > > > > > > > > > > > > > > > > > > Yes - in theory. In practice at most times on most roads I drive > > > > > > > there's > > > > > > > enough traffic and other reason to reduce your speed that in the > > > > > > > end > > > > > > > you > > > > > > > won't spend a lot of time at 100+ mph and therefore your time > > > > > > > saving > > > > > > > is > > > > > > > relatively minor. You will spend a lot of time accelerating to > > > > > > > this > > > > > > > kind > > > > > > > of speed and that is expensive in gas. > > > > > > > > > > > > > > Real world numbers I pushed a car capable of 140mph on german > > > > > > > highways > > > > > > > for a trip of about 3 hours and won about 15 minutes. Cost a lot > > > > > > > of > > > > > > > stress and a fill up (which cost those fifteen minutes). Not > > > > > > > worth it > > > > > > > for me. Maybe different on other roads and conditions. > > > > > > > > > > > > so you think you wouldn't have had to fill up if you only went 90? > > > > > > > > > > Assuming a car engine that is as efficient at 140 as 90, it is going > > > > > to > > > > > use 2.4 times as much fuel at 140. > > > > > > > > Let's look at a specific case: > > > > > > > > My Miata gets about 500km on a tank at 100 kph. So each 500 km would > > > > involve one fuel stop of -- counting getting off the highway, fueling > > > > up > > > > and getting back to speed -- ten minutes. That reduces my average speed > > > > to 500/(5 + 1/6) kph. > > > > > > > > In fact, you can generalize to: > > > > > > > > e: fuel economy in kilometres per litre. > > > > > > > > t: tank capacity in litres > > > > > > > > s: speed in kilometre per hour > > > > > > > > f: fueling time in hours > > > > > > > > V: average speed. > > > > > > > > V = et/(et/s + f) > > > > > > > > Which in this instance equals 96.8 kph. > > > > > > > > Now, if we raise the speed to 120 kph, we know that power (and thus > > > > roughly fuel flow per unit time) will rise with the square of that > > > > increase, but distance travelled will also rise in proportion, so fuel > > > > economy will fall in inverse proportion to the increase in speed > > > > (approximately)[1]. So at 1.2 times the speed, my Miata should get > > > > something like 416.7km on a fill. > > > > > > > > Plugging that figure into our equation... > > > > > > > > V = 416.7(416.7/120 + 1/6) = 114.5kph > > > > > > > > So how about 160kph (getting close to as fast as my Miata can go): > > > > > > > > 500/(160/100) = 312.5 kilometres on a tank and > > > > > > > > V = 147.42 kph. > > > > > > > > What about 200kph? > > > > > > > > 250 kilometres on a tank and V = 250/(250/200 + 1/6) = 176.5kph. > > > > > > > > Still faster point to point. > > > > > > > > How about 400 kph? Insane, I know, but this is all somewhat > > > > hypothetical. > > > > > > > > 125 kilometres per fill and an average speed of 260.9 kph. > > > > > > > > Now, what if we *double* the fill time? > > > > > > > > 100kph now gives 93.75kph average. > > > > > > > > 120kph gives 109.5 > > > > > > > > 160 gives 136.7 > > > > > > > > 200: 157.9 > > > > > > > > 400: 193.54 > > > > > > > > So, as long as you don't mind paying the cost, don't worry about the > > > > argument that you shouldn't drive faster because it will end up taking > > > > you longer because of the time you lose filling up. > > > > > > > > [1] This webpage shows that my linear relationship between speed and > > > > fuel economy isn't far off. If anything it shows that the relationship > > > > actually favours faster speeds: > > > > > > > > <http://www.recumbents.com/wisil/demma/superMileageVehicle.htm> > > > > > > That would work on straight unrestricted roads, but where does one find > > > one of those??? > > > Start adding bends with (say 80km/hr) restrictions and all your examples > > > have to brake and accelerate back to cruising speed - gurgle gurgle > > > gurgle ;-) Around here, if I drive at 100km/hr I just catch up to the > > > next block of cars travelling at 70-95km/hr. > > > > There are lots of places where you can cruise along a highway at > > significantly above the speed limit and never need to brake. > > It's not advisable in NZ, between hidden speed cameras and numerous > police patrols. > Each 10km above gets a fine, 130km looses your licence. > :-( Which has absolutely nothing to do with what is under discussion. > > > > > Even where you *do* need to brake, it isn't going to change the basic > > premise. > > Acceleration uses a lot of fuel. Actually, not particularly. Acceleration uses fuel, yes. > > > > > -- > > Alan Baker > > Vancouver, British Columbia > > "If you raise the ceiling four feet, move the fireplace from that wall > > to that wall, you'll still only get the full stereophonic effect if you > > sit in the bottom of that cupboard." -- Alan Baker Vancouver, British Columbia "If you raise the ceiling four feet, move the fireplace from that wall to that wall, you'll still only get the full stereophonic effect if you sit in the bottom of that cupboard." |
#38
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Europe Considers BAN ON SPORTS CARS to Combat Global Warming
Fred G. Mackey > wrote:
>> >> Rising speed decreases mileage. Very quick. > > I'm not disputing that even though I have to endure your poor grasp of > the English language. Sorry. I know my vocabulary is limited, as is my grammar and I build sentences using funny words. It's my fourth language. I'd be more comfortable communicating in three other languages and less comfortable in one. Feel free to correct me, I'm always eager to learn. > Driving at 90 for more than 3 hours is likely going to cause most > drivers to have to stop for gas. Not necessarily - my Peugeot 307SW was at around 8 l/100 km at 150km/h. 3 hours there is around 450 km, which is around 36 Liters. Quite some left in the tank. However, unless it's a reasonably empty highway where cruise control drives the car, it will make for a stressful drive keeping that kind of average speed, and it'll make mileage decrease again, having to accelerate back to that speed after every truck or slower car holding you up, so you're probably glad for a break after three hours. cu .\\arc |
#39
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Europe Considers BAN ON SPORTS CARS to Combat Global Warming
"Fred G. Mackey" > wrote in message . .. > Driving at 90 for more than 3 hours is likely going to cause most > drivers to have to stop for gas. That is only 270 miles. I am pretty sure even at 90 mph, I could go at leat 360 miles (4 hours) with my current car. Besides, unless I am alone, I've never been able to drive for more than 3 or 4 hours at a stretch before someone whats to stop for food, to stretch their legs, or use the restroom. Ed |
#40
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Europe Considers BAN ON SPORTS CARS to Combat Global Warming
Bernd Felsche > wrote:
> >>You don't notice really when you spend only a minute or two 'up >>there'. Once you're at >>100 mph for an hour, you'll notice how >>quickly the gas gauge starts to drop. > > Depends what you're driving and the conditions. > > A few weeks ago, I was driving an Audi A3 TDI on the Autobahn at > 170km/h and the fuel consumption was at 7.0 l/100km... so the 55 > litre fuel tank would have allowed almost 800km of cruising at that > speed without the need to refuel. Friend of mine drives the A3, 140hp TDI. Her mileage display is always around a liter better than reality. Just for info ;-) But even with 8, yes, indeed, consumption is not huge. However the same car driven at 120-130 will deliver 6 or lower. cu .\\arc |
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