No, I think YOU don't understand. Proportional means that there is a CONSTANT of proportionality. In the case of engines, there is no such constant because:
Different gear ratios will cause big differneces between the ratio of engine torque and accelleration
Even considering the same gear ratio, factors such as transmission loss, drag, etc. will mean that there is no constant ratio between accelleration and torque.
Hint: if you have to say that the CONSTANT of proportionality changes, then it is not proportional.
I thought the comment was that torque causes acceleration. This isn't the same as saying that torque is a measurement of acceleration. Gravity causes things to fall to the ground, but it isn't a measurement of falling.
I agree that many US cars score in the kW/$ stakes and can outrun many European cars in a straight line. Even Jeremy Clarkson agrees with that. However, I must say I recollect driving a (what I thought large) car many years ago in the US that had a massive 300 cubic in (c. 5 l) and at just above 90 mph it ran out of puff, whereas our humble family Opel Rekord (GM) and its 1700 cc engine was good for 100 mph. Of course things have moved on but the essence remains.
Engine efficiency is kW/unit volume and many US engine just don't compete. At the end of the day it is a matter of horses for courses and the engines developed in different environments (demands on cars, fuel prices, taxes etc).
Bang per buck does not necessarily refer to a literal buck :-)
DAS
For direct contact replace nospam with schmetterling
You STILL don't get it, do you? When you shift gears, the constant multiplier between engine torque and wheel-to-ground force changes, but the force at the rear wheels is STILL directly proportional to engine torque. That is ALWAYS true, regardless of gear ratio- increase engine torque, and acceleration increases.
No, that wasn't the point at all. The point was comparing a car (or almost identical class of car) with an "American engineering" approach (v8, solid axle, etc.) to a "European engineering" approach (which is specious, because there are many big torquey European v8s, but I accepted the original as stated for debate purposes). You can't arbitrarily start saying "let's use a Miata sized car instead of a Mustang for comparison."
"Proportionality" is preserved across a constant multiplier. Its not preserved against non-linear operators (exponents, logarithms, trigonometric operators, etc.). Gear ratios are constant multipliers, therefore proportionality is preserved: if you double the engine torque, you double the wheel torque, no matter whether or not the intervening gear ratio is 2.76:1 or 5000:1. Its STILL proportional.
I disagree with great vehemence ;-) The ONLY measure of efficiency is kW output/(BTU/hour) input. Or in the case of a complete vehicle, its miles/gallon or liters/km. It doesn't matter if you get 30 MPG from a
3.5L engine as an Intrepid does or from a 7L engine as the Corvette does.
Agreed on that point. But the argument that there is any "technological merit" in high horsepower/displacement numbers has always been bogus. In fact, it has many DISadvantages (long term reliability being the most obvious).
See that: "CONSTANT RATIO". It does not say "constant ratio if you ignore factors that cause the ratio to vary".
In any case, even if you ignore the differences due to different gear ratios, there are also many other facts such as drag, transmission losses, etc, which mean that even in the restricted case of a single gear, accelleration is not proportional to torque (although it will be close for a narrow range of speeds).
Go back to the original article. It was discussing the merits of cars designed in US and Europe -- there was nothing that limited the discussion to similar types of cars. In fact, the point of the article is that the different markets has produced substantially different cars -- lightweight cars with good dynamic handling in Europe vs. heavy cars with large engines that have very good straight line performance in the US.
Having read the original article, then read the first comment on it by MoPar Man:
See that: he directly relates accelleration to torque in the context of dicsussing different types of cars. My point has been all along that torque is a different measurement than accelleration -- that accelleration is a factor of many things, only one of which is torque, the other major factors being gearing ratios, power curves, and overall mass.
If you have a 5.0 in a lincoln continental or grand marquis (about as big as America builds)it will (in many cases) have a "governed" top end of 145kph - or 90mph which is part of the emissions system. Nothing to do with the power of the engine. Same engine in a Mustang MAY have the same limitation. My 3.0 liter Aerostar "hit the wall" at 140kph. Pulled pretty strong right 'till it hit the governor.
Prior to emission controls and "big brother" getting involved, I had several 225 inch sixes that would do over 105 MPH. ( and one 170 inch (2.7 liter) that did well over 120) They were American. The big difference between the 8 and the six (and the Rekord wagon) is how quickly it got to 90. The 1700 Rekord didn't set any "records" getting there. I've driven them.
If you are going to insist on twisting the original poster's words to make him mean "torque is the same thing as acceleration" rather than "more torque gives better acceleration" which is what he said IN CONTEXT, then you win by default. Congratulations. You win the pedantic award for this month.
Now look what you did. You got everyone in an uproar discussing horsepower and torque. It is actually quite comical, thanks!
For the casual reader, let me say that horsepower is torque x RPM. Same thing as Watts = Volts X Amps.
For example, I can easily produce 1000 ft lbs of torque using a bicycle attached to a gear box having a 100:1 ratio. With this I can lift a 1000 lb load, though not very fast. Reverse this set up and I can easily spin a shaft at 10,000 RPM, with no load attached. With this in mind, read the discussions and have a good laugh.
That's nice -- fall back on ad-hominem when your argument fails.
However, to respond: I notice that you did not include the text that I pulled from the orginal posting and put in my last response. The text that shows quite clearly that the OP was directly equating torque and accelleration. Now why would you not include it? Perhaps because it shows that you are wrong?
Other people in this newsgroup have accepted that the OP was making such an equation.
I did not know that speeds are governed at such low levels (even in the
70s?). Those European cars that are limited are so at no lower than 155 mph (250 km/h).
I also vaguely recollect putting my foot down at lower speeds and hearing a very satisfying whawhawha but not any quick reaction...
Still, I am sure that has changed. The cars I have had more recently in North America have been more 'normal' by my standards and I haven't tried to push them to 100 mph plus.
A couple of years ago I had arranged a Hertz Mustang but the bar stewards would not let me take the car away when I produced my licence. The British one has two parts, the main one being a credit-card-type object with photo and signature, and a second part that is a piece of paper that, among other things, lists one's traffic offences. Unbeknownst to me at the time Hertz insists on seeing this, but I did not and do not carry it, as the other rental companies don't demand it. I wound up with a Budget box-on-4-wheels from Korea..
So I never got the Mustang... (I have mentioned this incident before in this NG, so sorry of it's a repeat to you.). I was all ready to enjoy its performance, as I had many miles ahead of me...
BTW, our 12-year-old two-litre (Merc 190E) gets to 100 mph very quickly and doesn't take much longer for the next 15 mph (indicated, not calibrated).
DAS
For direct contact replace nospam with schmetterling
It is human nature to justify our decisions and opinions, and this article demonstrates this principle. This is the fundamental reason why opinion surveys such as those conducted by Consumer Reports and JD Power & Assoc. are worthless.
The article is poorly written, and really showcases the author's limited knowledge about the subject matter. It lacks meaningful content.
The first half is an empty rant aimed at US car makers. The second half being somewhat of a review of the new Ford Mustang. The latter contains no data to support the author's opinions.
Even though the author regards US cars to be the scum of the earth, in the end they are tempted to purchase a Ford Mustang. Very wishy-washy in my opinion.
The only positive things I found in the article are the grammar and spelling.
Quotes are from article in question, followed by comments.
"The new Pontiac Solstice is America's first attempt at making a sports car in more than 50 years."
The opening sentence reveals what little the author knows about the US market. The rest of the article seems to confirm this for me. Perhaps the sales of US cars in the UK is on the upswing and this article is an attempt at damage control.
"Alfa Romeo can make a sports car using steel so thin you can read through it ..."
This is good? Sounds like they do not perform crash safety tests in the UK. I would like to see a comparison of fatal crashes to population for the US and UK car makers.
"As a result we still have an innate sense that a car is something you save up for."
And in the UK, because of the cost you are stuck with that car for a long time. The US market is completely different. We like variety and change cars every three to five years. I believe the US market reflects consumer demand.
"In Europe we talk about style and how fast a car accelerates..."
I find it amazing that only Europe talks about style and acceleration. Seems to confirm my comments in the first paragraph, doesn't it?
"If you do encounter someone over there [US] who's fond of performance cars they're only really interested in how much g can be generated in the bends, whereas here [UK] those of a petrolhead disposition don't care at all about grip, only what happens when it's lost and the car is sliding. Then you are into the world of handling. A world where nothing but skill keeps you out of the hedge."
More Gs in the bends would keep the UK drivers out of the hedge, don't you think? I would bet the author majored in liberal arts and knows nothing about cars, other than how to start one. Probably refills at a full service station. I would love to hear their explanation of horsepower and torque. :O
"From day one American motor sport was all about sponsorship, which is why the oval raceway was developed."
Why is this bad? I don't know this for a fact, but I would bet the US has more forms of racing than any other country. We can do this because sponsorship pays for it. Racing is a great way for manufacturers to prove their designs, US and foreign.
"Add all this together and you start to understand why we have Lotus, Ferrari, Maserati and Aston Martin. And they have the Ford F-150 Lightning pick-up truck: 0-60mph in a millionth of a second. Enough space in the back for a dead bear. And on a challenging road about as much fun as a wasabi enema."
Now the author is comparing a pickup truck to sports cars. I feel so embarrassed for them.
The author doesn't mention any of the British Leyland brands. Did they go bankrupt? Mention Lucas Electronics to any mechanic familiar with UK cars and watch them run!
"They also have the Ford Mustang and last week that's what I was using to cruise up the 101 from Monterey to San Francisco"
The author has been to the US once and rented a Ford Mustang, and is using this experience as the basis for this article.
"There's no complex double-stage turbocharging here; no elegantly machined swirl chamber to extract the best possible power and economy from the smallest possible engine"
Probably learned about these terms from a car magazine while waiting for the Mustang to be refueled.
The Mustang is built Ford cheap. Ford uses the cheapest design possible to accomplish the goal, even if it means the engine will blow spark plugs out through the hood. People buy Fords because they are cheaper. It's sad, but true.
"Its engine has wasteful, unused capacity that turns fuel into nothing"
Totally incorrect! There is no unused capacity. Ford HAS to use that large of an engine to produce 300 HP because of the cheap design. To produce 300 HP out of a 2.0L engine requires a much better engineering design, superior materials, precision manufacturing, and a much more sophisticated engine control system.
Personally, I would rather have diareaha than a Ford, of any kind. I have a '98 Mustang. It's built Ford cheap, and deserves to wear the Ford sad oval. But if a Flaccid 150 could go from "0-60mph in a millionth of a second" I would probably buy one, but only with an extended warranty.
I believe the Ford Mustang would best be described as a fantasy car; it is what the buyer imagines it to be. At least until a slightly tweaked 2.0L turbo charged Mitsubishi Eclipse blows its doors off!
Well, I haven't heard of it happening except when the water pump impeller lets go and the engine is overheated. Mine let go, but I caught it without overheating the engine. It is one sweet running little engine, and very strong for it's displacement. It IS a bit of a bear to work on, I'll admit - but the whole package is more than the sum of it's parts. A very nice handling machine in the european sporting tradition - yet quite practical.
Sadly, with a Mitz it's usually a few other parts it blows off - of itself.
I've had much worse luck with Mitz's than with fords. I've owned at least 3 of each, and currently own a Ford - would be hard pressed EVER to buy another Mitz. (would have to be almost free to make it anywhere near worth the hassle).
One of my favorite things to watch is when people discuss torque and horsepower on USENET. Honest!! That should be the number prohibition on here, from my experience.
To be honest, I think they lied. I have never heard of any mode of transportation other than a school bus being governed at such a low speed.
In the states, nothing really was governed that I can remember until about
1985 or later, and I do remember 126 mph way back then as being the starting point for things that had the first ever speed governors. This was of course to stop you before the break point for H speed-rated tires.
These days, probably everything is governed at some speed, and I couldn't possibly know what all those speeds are. But the era of 5.0 Litre Fords, mentioned in this thread, is long over. Back then, I am pretty sure you're right, governed speeds were pretty far above 100 mph.
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