|
|
| Acela Speed Question (1036951) | |
 |
|
| Home > SubChat | |
[ Post a New Response | Return to the Index ]
[1 2] |
||
|
|
Page 1 of 2 |
|
|
|
| (1036953) | |
Re: Acela Speed Question |
|
|
Posted by Chris R16/R2730 on Mon Feb 14 17:56:23 2011, in response to Acela Speed Question, posted by italianstallion on Mon Feb 14 17:48:22 2011. Acelas, like all Amtrak trains are limited on Metro North territory. Especially now that two of the tracks are closed around Fairfield. Acelas are really not worth the extra money for NY-Boston travel, unless you want the first class service. |
|
|
| (1036962) | |
Re: Acela Speed Question |
|
|
Posted by Broadway Lion on Mon Feb 14 18:10:56 2011, in response to Acela Speed Question, posted by italianstallion on Mon Feb 14 17:48:22 2011. And was the State Patrol on vacation today?
|
|
|
(Sponsored) |
iPhone 6 (4.7 Inch) Premium PU Leather Wallet Case - Red w/ Floral Interior - by Notch-It |
|
| (1036964) | |
Re: Acela Speed Question |
|
|
Posted by Olog-hai on Mon Feb 14 18:14:40 2011, in response to Acela Speed Question, posted by italianstallion on Mon Feb 14 17:48:22 2011. Any reason why not?Metro-North/Connecticut DOT ownership. Not in their interest to pay for ACSES on the ROW, Shoreliners, P32AC-DMs and EMUs out of pocket. They also claim that their track centers are too close together to allow Acela Express to use its active-tilt system without sideswiping a train on the adjacent track (that's in spite of the AE being two inches narrower than other passenger trains). |
|
|
| (1036968) | |
Re: Acela Speed Question |
|
|
Posted by TransitChuckG on Mon Feb 14 18:40:58 2011, in response to Re: Acela Speed Question, posted by Broadway Lion on Mon Feb 14 18:10:56 2011. I've driven I-95 in CT.I normally did 75-80, it's a blast. |
|
|
| (1036972) | |
Re: Acela Speed Question |
|
|
Posted by italianstallion on Mon Feb 14 18:53:17 2011, in response to Re: Acela Speed Question, posted by Broadway Lion on Mon Feb 14 18:10:56 2011. I drive this stretch round trip at least every 2 weeks. I have a pretty good idea where the State Police hang out. |
|
|
| (1036980) | |
Re: Acela Speed Question |
|
|
Posted by TransitChuckG on Mon Feb 14 19:15:35 2011, in response to Re: Acela Speed Question, posted by TransitChuckG on Mon Feb 14 18:40:58 2011. I've driven I-95 in CT.I normally did 75-80, it's a blast.The other thing is I get better gas mileage at those higher speeds, like 30-32 mpg as opposed to 26-27 mph at 55-60 MPH. My mechanic buddy told me the engine runs leaner at higher speeds. |
|
|
| (1036991) | |
Re: Acela Speed Question |
|
|
Posted by Randyo on Mon Feb 14 19:51:35 2011, in response to Re: Acela Speed Question, posted by TransitChuckG on Mon Feb 14 19:15:35 2011. Yet in the 1970s, the 55 MPH speed limit was imposed ostensibly to save gas. |
|
|
| (1037002) | |
Re: Acela Speed Question |
|
|
Posted by Terrapin Station on Mon Feb 14 20:30:08 2011, in response to Re: Acela Speed Question, posted by Randyo on Mon Feb 14 19:51:35 2011. Go figure... |
|
|
| (1037007) | |
Re: Acela Speed Question |
|
|
Posted by Dutchrailnut on Mon Feb 14 20:51:21 2011, in response to Re: Acela Speed Question, posted by Olog-hai on Mon Feb 14 18:14:40 2011. in two years MNCR will have ACSES but speeds on New Haven and other lines will stay same. |
|
|
| (1037057) | |
Re: Acela Speed Question |
|
|
Posted by New Flyer #857 on Tue Feb 15 08:30:40 2011, in response to Re: Acela Speed Question, posted by TransitChuckG on Mon Feb 14 19:15:35 2011. Almost every "gas saving tips" and related search I've ever made suggests otherwise, though I'm not ruling out the possibility that your mechanic has some first-hand wisdom. |
|
|
| (1037108) | |
Re: Acela Speed Question |
|
|
Posted by znufrii on Tue Feb 15 10:38:50 2011, in response to Re: Acela Speed Question, posted by Randyo on Mon Feb 14 19:51:35 2011. Engines were built differently back then as well, so that might well have been the case. |
|
|
| (1037129) | |
Re: Acela Speed Question |
|
|
Posted by Hank Eisenstein on Tue Feb 15 10:59:39 2011, in response to Re: Acela Speed Question, posted by New Flyer #857 on Tue Feb 15 08:30:40 2011. Newer cars do seem to use less gas at higher speeds, but there's a limit to it that depends on the car, and a number of other factors as well. For instance, when I go to southern NJ, I get better mileage going south than north, given the same average speed (the car computer calculates this). I think it's because I'm going more downhill than uphill, but I don't currently have a tool to measure the elevation changes on the trip. |
|
|
| (1037130) | |
Re: Acela Speed Question |
|
|
Posted by Hank Eisenstein on Tue Feb 15 11:00:23 2011, in response to Re: Acela Speed Question, posted by italianstallion on Mon Feb 14 18:53:17 2011. That and when you go 55 while the slowest traffic is doing 70, you get angry looks. |
|
|
| (1037136) | |
Re: Acela Speed Question |
|
|
Posted by Terrapin Station on Tue Feb 15 11:10:42 2011, in response to Re: Acela Speed Question, posted by TransitChuckG on Mon Feb 14 19:15:35 2011. The other thing is I get better gas mileage at those higher speeds, like 30-32 mpg as opposed to 26-27 mph at 55-60 MPH. Is it possible that in situations where you are going 55-60 you are much more likely to be encountering congestion or stop lights that would result in decreased fuel economy (vs. 55-60 MPH steady state operation) and that in situation where you are going 75-80 you are most likely able to continue at 75-80 for long periods of time, optimizing fuel economy but resulting in a number than would be lower than 55-60 steady for the same distance? |
|
|
| (1037138) | |
Re: Acela Speed Question |
|
|
Posted by Terrapin Station on Tue Feb 15 11:11:50 2011, in response to Re: Acela Speed Question, posted by Hank Eisenstein on Tue Feb 15 10:59:39 2011. Newer cars do seem to use less gas at higher speeds While your statement is very vague, if you mean that newer cars can get better gas mileage at 75-80 than at 55-60, then based on everything I have read, I don't think that is very likely. |
|
|
| (1037141) | |
Re: Acela Speed Question |
|
|
Posted by TransitChuckG on Tue Feb 15 11:17:39 2011, in response to Re: Acela Speed Question, posted by New Flyer #857 on Tue Feb 15 08:30:40 2011. Almost every "gas saving tips" and related search I've ever made suggests otherwise, though I'm not ruling out the possibility that your mechanic has some first-hand wisdom.That's what baffles me, why it's better at 80 mph. I have to take what I hear from my mechanic friend with a grain of salt. I should really do some research on it. Oh, I forgot, I'm a dumb-ass, My college degree got me a good job, but I'm still an idiot. |
|
|
| (1037142) | |
Re: Acela Speed Question |
|
|
Posted by Olog-hai on Tue Feb 15 11:17:53 2011, in response to Re: Acela Speed Question, posted by Dutchrailnut on Mon Feb 14 20:51:21 2011. . . . so the track classes aren't going up, in that case . . . ? |
|
|
| (1037148) | |
Re: Acela Speed Question |
|
|
Posted by New Flyer #857 on Tue Feb 15 11:34:20 2011, in response to Re: Acela Speed Question, posted by TransitChuckG on Tue Feb 15 11:17:39 2011. Simple Internet searches may not be the ideal form of research, but you can weigh the source and reasoning for something posted on the Internet, engage in dialogue with your mechanic, and let the various opinions stand up against each other to reach a practical decision.Wikipedia, for example, is labeled non-dependable because it can be edited by anyone at all, but someone took the time to edit, and, in many cases, cite sources. Let the reader process it. Sadly college degrees are all about the job nowadays. Let me try to get this back to subways: Does the regenerative braking feature on the newer trains mean that the train is actually saving energy by running local instead of express (the opposite being the case on the older trains)? Hybrid cars, I understand, give an unconventionally better rating to city street driving than highway driving in terms of mpg. |
|
|
| (1037151) | |
Re: Acela Speed Question |
|
|
Posted by New Flyer #857 on Tue Feb 15 11:37:50 2011, in response to Re: Acela Speed Question, posted by Terrapin Station on Tue Feb 15 11:11:50 2011. Agreed. My car manual notes that 45 to 60 make up optimum gas efficiency range. Of course, manuals and other official gas-saving guides may only be telling you this to make you less interested in speeding. Still, it makes sense. You do a lot more accelerating and braking to get up and down from those higher speeds. |
|
|
| (1037152) | |
Re: Acela Speed Question |
|
|
Posted by Teddmann on Tue Feb 15 11:38:35 2011, in response to Re: Acela Speed Question, posted by TransitChuckG on Tue Feb 15 11:17:39 2011. Fuel economy at steady speeds with selected vehicles was studied in 2010. The most recent study indicates greater fuel efficiency at higher speeds than earlier studies; for example, some vehicles achieve better mileage at 65 than at 45 mph (72 rather than 105 km/h), although not their best economy, such as the 1994 Oldsmobile Cutlass, which has its best economy at 55 mph (29.1 mpg), and gets 2 mpg better economy at 65 than at 45 (25 vs 23 mpg). All cars demonstrated decreasing fuel economy beyond 65 mph (105 km/h), with wind resistance the dominant factor, and may save up to 25% by slowing from 70 mph (110 km/h) to 55 mph (89 km/h). However, the proportion of driving on high speed roadways varies from 4% in Ireland to 41% in Netherlands.There were complaints when the U.S. National 55 mph (89 km/h) speed limit was mandated that it could lower, instead of increase fuel economy. The 1997 Toyota Celica got 1 mpg better fuel-efficiency at 65 than it did at 55 (43.5 vs 42.5), although almost 5 mpg better at 60 than at 65 (48.4 vs 43.5), and its best economy (52.6 mpg) at only 25 mph (40 km/h). Other vehicles tested had from 1.4 to 20.2% better fuel-efficiency at 55 mph (89 km/h) vs. 65 mph (105 km/h). Their best economy was reached at speeds of 25 to 55 mph (see graph). 
|
|
|
| (1037153) | |
Re: Acela Speed Question |
|
|
Posted by New Flyer #857 on Tue Feb 15 11:39:11 2011, in response to Re: Acela Speed Question, posted by Terrapin Station on Tue Feb 15 11:10:42 2011. Good insight. |
|
|
| (1037155) | |
Re: Acela Speed Question |
|
|
Posted by LA Scott on Tue Feb 15 11:42:20 2011, in response to Re: Acela Speed Question, posted by TransitChuckG on Mon Feb 14 19:15:35 2011. Engines tend to run better at higher speeds, but as speeds go up so does air resistance.That means that MPG will go up with speed to a point where the efficiency gained by higher speeds will be balanced with the extra energy needed to overcome wind resistance. Faster than that, and the MPG goes down. One of the reasons that Hybrids do better in the city than the highway is that the regenerative breaking captures/reuses much of the energy wasted by deceleration/acceleration and low speeds, while the top speeds are not enough to enter the zone where efficiency goes down. |
|
|
| (1037156) | |
Re: Acela Speed Question |
|
|
Posted by LA Scott on Tue Feb 15 11:44:59 2011, in response to Re: Acela Speed Question, posted by LA Scott on Tue Feb 15 11:42:20 2011. What I posted also ignores the impact of what gear the vehicle is in, which also has an impact on MPG. |
|
|
| (1037157) | |
Re: Acela Speed Question |
|
|
Posted by TransitChuckG on Tue Feb 15 11:45:37 2011, in response to Re: Acela Speed Question, posted by Terrapin Station on Tue Feb 15 11:10:42 2011. Very good analysis. It's very difficult to determine the congestion factor at either speed I talked about. My statement should have said little or no congestion and no stop lights. I drove very fast on I-95 in CT with hardly any slow downs. Same thing for my 55-60 stretch on my express roads in PA.I filled my tank and did a mileage check after each of these runs.So it varies..... |
|
|
| (1037160) | |
Re: Acela Speed Question |
|
|
Posted by Terrapin Station on Tue Feb 15 11:55:20 2011, in response to Re: Acela Speed Question, posted by New Flyer #857 on Tue Feb 15 11:37:50 2011. Agreed. Thank you. |
|
|
| (1037161) | |
Re: Acela Speed Question |
|
|
Posted by Terrapin Station on Tue Feb 15 11:57:34 2011, in response to Re: Acela Speed Question, posted by New Flyer #857 on Tue Feb 15 11:39:11 2011. Good insight. Thank you. |
|
|
| (1037162) | |
Re: Acela Speed Question |
|
|
Posted by Terrapin Station on Tue Feb 15 11:59:29 2011, in response to Re: Acela Speed Question, posted by TransitChuckG on Tue Feb 15 11:45:37 2011. Very good analysis. Thank you. My statement should have said little or no congestion and no stop lights. I drove very fast on I-95 in CT with hardly any slow downs. Same thing for my 55-60 stretch on my express roads in PA.I filled my tank and did a mileage check after each of these runs. It just simply does not make any sense that with all things being equal, as you are seemingly describing, that you would get better gas mileage at 75-80 than at 55-60. |
|
|
| (1037164) | |
Re: Acela Speed Question |
|
|
Posted by TransitChuckG on Tue Feb 15 12:08:02 2011, in response to Re: Acela Speed Question, posted by Terrapin Station on Tue Feb 15 11:59:29 2011. You are right, it makes no sense, but it happened. I wish I still had my book of recorded trips and gas mileage calculations.I believe I threw it away. |
|
|
| (1037166) | |
Re: Acela Speed Question |
|
|
Posted by Fytton on Tue Feb 15 12:14:24 2011, in response to Re: Acela Speed Question, posted by New Flyer #857 on Tue Feb 15 11:34:20 2011. Does the regenerative braking feature on the newer trains mean that the train is actually saving energy by running local instead of express?The answer has to be no. You can't get energy out of nowhere - that would breach the laws of thermodynamics. Necessarily, the energy used by accelerating away from each additional station stop would be more than the energy gained by slowing down regeneratively at each stop. |
|
|
| (1037167) | |
Re: Acela Speed Question |
|
|
Posted by Fisk Ave Jim on Tue Feb 15 12:17:40 2011, in response to Re: Acela Speed Question, posted by TransitChuckG on Tue Feb 15 12:08:02 2011. A big factor in high speed gas mileage is the transmission. Say for example your your doing 55mph & your tach reads 3000 rpm, & your transmission has a 5th or 6th speed overdrive. Shift up to the higher gear and say do 75, your tach, depending on the vehicle in most cases will go down to say 2800-2900 rpm. With your engine turning less, in theory your milage should improve even at the higher speed. |
|
|
| (1037169) | |
Re: Acela Speed Question |
|
|
Posted by Charles G on Tue Feb 15 12:22:36 2011, in response to Re: Acela Speed Question, posted by Hank Eisenstein on Tue Feb 15 11:00:23 2011. Just put a ramp on the back of your car and let them go right over you... |
|
|
| (1037171) | |
Re: Acela Speed Question |
|
|
Posted by Terrapin Station on Tue Feb 15 12:27:02 2011, in response to Re: Acela Speed Question, posted by Fisk Ave Jim on Tue Feb 15 12:17:40 2011. A big factor in high speed gas mileage is the transmission. Say for example your your doing 55mph & your tach reads 3000 rpm, & your transmission has a 5th or 6th speed overdrive. Shift up to the higher gear and say do 75, your tach, depending on the vehicle in most cases will go down to say 2800-2900 rpm. With your engine turning less, in theory your milage should improve even at the higher speed. Jim, I think we can assume that in Chuck's automatic transmission equipped Altima (afaik), at a steady 55-60 MPH, the transmission is already in the highest gear (assuming it is the most efficient gear for that speed, which I believe it would be). So the transmission does not play a part as you described. Take Pride,
|
|
|
| (1037172) | |
Re: Acela Speed Question |
|
|
Posted by TransitChuckG on Tue Feb 15 12:27:28 2011, in response to Re: Acela Speed Question, posted by Fisk Ave Jim on Tue Feb 15 12:17:40 2011. That's what my mechanic buddy just told me, he asked was your tach reading? I wish I could remember. Next time I'll watch the tach.The vehicle I drive is a 2003 Nissan Altima 2.5 c.i. , F.I, 4 cyl automatic. I love it. 
|
|
|
| (1037173) | |
Re: Acela Speed Question |
|
|
Posted by Terrapin Station on Tue Feb 15 12:28:45 2011, in response to Re: Acela Speed Question, posted by Hank Eisenstein on Tue Feb 15 11:00:23 2011. I usually don't see the faces of other drivers, let alone drivers who are passing by at 70 MPH. So.... |
|
|
| (1037174) | |
Re: Acela Speed Question |
|
|
Posted by Terrapin Station on Tue Feb 15 12:30:25 2011, in response to Re: Acela Speed Question, posted by TransitChuckG on Tue Feb 15 12:27:28 2011. You mean 2.5L, not 2.5 c.i. |
|
|
| (1037175) | |
Re: Acela Speed Question |
|
|
Posted by TransitChuckG on Tue Feb 15 12:31:01 2011, in response to Re: Acela Speed Question, posted by Terrapin Station on Tue Feb 15 12:30:25 2011. Yes, that was an oops! |
|
|
| (1037178) | |
Re: Acela Speed Question |
|
|
Posted by LA Scott on Tue Feb 15 13:03:07 2011, in response to Re: Acela Speed Question, posted by Terrapin Station on Tue Feb 15 12:30:25 2011. I would be impressed if it hit 75 MPH with a 2.5 c.i engine. |
|
|
| (1037181) | |
Re: Acela Speed Question |
|
|
Posted by znufrii on Tue Feb 15 13:06:48 2011, in response to Re: Acela Speed Question, posted by Teddmann on Tue Feb 15 11:38:35 2011. Fascinating. Would love to see a newer study with more modern cars to compare. I'd imagine that improvements in aerodynamics and engine design would strongly mitigate the downward slope at higher speeds. |
|
|
| (1037182) | |
Re: Acela Speed Question |
|
|
Posted by Terrapin Station on Tue Feb 15 13:10:30 2011, in response to Re: Acela Speed Question, posted by znufrii on Tue Feb 15 13:06:48 2011. I'd imagine that improvements in aerodynamics and engine design would strongly mitigate the downward slope at higher speeds. Why? It might improve things a little bit but "strongly mitigate" is going way too far, IMO. |
|
|
| (1037183) | |
Re: Acela Speed Question |
|
|
Posted by New Flyer #857 on Tue Feb 15 13:11:38 2011, in response to Re: Acela Speed Question, posted by Fytton on Tue Feb 15 12:14:24 2011. Makes sense to me, but how do hybrid cars receive a higher city mpg rating than highway mpg rating, then? |
|
|
| (1037187) | |
Re: Acela Speed Question |
|
|
Posted by znufrii on Tue Feb 15 13:17:48 2011, in response to Re: Acela Speed Question, posted by Terrapin Station on Tue Feb 15 13:10:30 2011. That would be precisely the point of putting the idea to the test to find out. |
|
|
| (1037194) | |
Re: Acela Speed Question |
|
|
Posted by Terrapin Station on Tue Feb 15 13:27:31 2011, in response to Re: Acela Speed Question, posted by znufrii on Tue Feb 15 13:17:48 2011. But you already provided a possible outcome that you think likely. I'm asking why you think that is so. You don't need to do the study for that. |
|
|
| (1037197) | |
Re: Acela Speed Question |
|
|
Posted by znufrii on Tue Feb 15 13:32:42 2011, in response to Re: Acela Speed Question, posted by Terrapin Station on Tue Feb 15 13:27:31 2011. I don't know. Why is it so important to you? |
|
|
| (1037199) | |
Re: Acela Speed Question |
|
|
Posted by Terrapin Station on Tue Feb 15 13:38:48 2011, in response to Re: Acela Speed Question, posted by znufrii on Tue Feb 15 13:32:42 2011. Huh? This is a discussion forum. You put forth an idea and I put forth another idea and asked you the reasoning behind your idea. Is there something wrong with that? Is that not what is done on discussion forums? |
|
|
| (1037201) | |
Re: Acela Speed Question |
|
|
Posted by Hank Eisenstein on Tue Feb 15 13:43:06 2011, in response to Re: Acela Speed Question, posted by Terrapin Station on Tue Feb 15 13:27:31 2011. A possible outcome...a hypothesis...does indeed need a study (or experiment) to prove the outcome. Basic scientific method.hy·poth·e·sis 1. a proposition, or set of propositions, set forth as an explanation for the occurrence of some specified group of phenomena, either asserted merely as a provisional conjecture to guide investigation (working hypothesis) or accepted as highly probable in the light of established facts. 2. a proposition assumed as a premise in an argument. 3. the antecedent of a conditional proposition. 4. a mere assumption or guess. |
|
|
| (1037203) | |
Re: Acela Speed Question |
|
|
Posted by Terrapin Station on Tue Feb 15 13:46:49 2011, in response to Re: Acela Speed Question, posted by Hank Eisenstein on Tue Feb 15 13:43:06 2011. No. I already said:a possible outcome that you think likely. I'm asking why you think that is so. You don't need to do the study for that. You don't need a study to explain why you think something is so. Please try to pay attention Hank. |
|
|
| (1037205) | |
Re: Acela Speed Question |
|
|
Posted by znufrii on Tue Feb 15 13:48:54 2011, in response to Re: Acela Speed Question, posted by Terrapin Station on Tue Feb 15 13:38:48 2011. Sure. I just found it curious that you ignored the substance of my post -- specifically whether there was a similar study done with more recent cars -- and instead chose to concern yourself with a minor rhetorical aside. |
|
|
| (1037207) | |
Re: Acela Speed Question |
|
|
Posted by Terrapin Station on Tue Feb 15 14:03:10 2011, in response to Re: Acela Speed Question, posted by znufrii on Tue Feb 15 13:48:54 2011. I just found it curious that you ignored the substance of my post -- specifically whether there was a similar study done with more recent cars I ignored it because I don't know anything off-hand about any more recent studies, nor am I prepared to start doing in depth research to find out (i.e. beyond Googling, which you could do yourself). Presumably the person who posted the old study would be in the best position to find a newer study. and instead chose to concern yourself with a minor rhetorical aside. What you wrote wasn't minor, rhetorical, or an aside. You put forth the hypothesis that modern cars would show huge improvements. So I asked why you thought that. Again, what is abnormal or wrong about that? And how come you are very resistant to explaining the reasoning behind your hypothesis? I thought it was a simple question about a simple statement you made. I don't see why you needed to drag it out like this. |
|
|
| (1037215) | |
Re: Acela Speed Question |
|
|
Posted by WayneJay on Tue Feb 15 14:21:17 2011, in response to Re: Acela Speed Question, posted by New Flyer #857 on Tue Feb 15 13:11:38 2011. Hybrid cars do better in the city because they're using their electric motor more than they're using the gasoline engine. Think about it. The gasoline engine shut off at a complete stop. Many hybrid vehicles (especially those from Toyota) will accelerate from a complete stop on the electric motor and then the gasoline engine starts once it reaches a certain speed or sooner under heavy throttle. Also, many will use only the electric motor at low speeds.The accelerating part probably is most significant in the high MPG because a conventional gasoline vehicle uses the most fuel when accelerating until it gets up to speed. Also, in city driving the transmission is doing lots of back in forth in low gears which again is where the most fuel consumption takes place. On the highway it's nothing special because then the hybrids are like any other vehicle at speed. |
|
|
[1 2] |
||
|
|
Page 1 of 2 |
|
