I live in Tasmania, Australia. Mountains are city driving.
I was always taught to drive as if the car could fail at any second. Because, you know, it could. Modern mechanicals aside, I'm directing the momentum of a 1.2 metric tonne lump of steel at speeds above 100kpmh. Treating that with anything less than utter respect leads to disaster.
Excuse me while I see to my own safety, and that of those around me.
tylernt covers the "full throttle" component of this in another reply to your post.
I'm an Australian, and the son of an engineer who restores old vehicles for a living. We have British, Italian and Japanese vehicles. We have never owned an American vehicle.
The BMW data was almost certainly collected for their vehicles, which almost uniformly (at the time of the study) used straight 4 or straight 6 engines. 75% throttle would have been a rough figure arrived at for their own machines, I would imagine.
It is patently obvious that applying more throttle increases the amount of fuel used per second. However, the amount of fuel used is not a direct 1:1 to your acceleration.
The trick here is not that you use less fuel to reach your desired speed by accelerating harder. That's nonsense, and an incorrect understanding of the problem. Accelerating harder may well use more fuel to reach your desired speed. The trick is in how much time your spend at you desired speed, not accelerating.
If you do the calculus on this, you'll note that with the rapid acceleration model, you spend a far greater time at your desired target speed over the course of your journey. While at that speed, you are not accelerating. You will use more fuel accelerating quickly than accelerating slowly, per unit of time. However, your overall time spent not accelerating but simply maintaining speed more than compensates.
I assume that if you do have brakes of that sort, you'll be using them correctly.:) You'd probably have a fair to reasonable working knowledge of cars and car driving if you had a machine that used carbon ceramic discs!
To be fair, though, that type of brake can still overheat and shatter.
It's counter-intuitive, but relatively rapid acceleration is far better than slow acceleration.
A long, slow acceleration up to a target speed will use more fuel than a rapid acceleration up to a target speed. This is regardless of the vehicle's horsepower or torque.
Downhill coasting I've covered in other posts in this thread. Suffice it to say that brakes are a safety feature that you don't to have missing in an emergency.
Brakes are a safety device; you need them for keeping the car stationary, bringing it to a stop from low speeds, to prevent emergency situations from occurring, and for use in an emergency situation itself.
You save them; you don't use them. If you use your brakes as a matter of course, to control your speed, then you won't have them when you need them, due to heat build-up. No, disc brakes won't save you - they're better than drum, but they still heat up and loose effectiveness. No, ABS won't save you, either. It still has nothing to play with if your brakes have heated up.
Which would you rather: a bit of fuel economy (dubious anyway), or a large funeral bill?
Holding in your clutch a lot will stuff your throw-out race. That's really bad, because that'll lead to a clutch that you can't engage or disengage. Not having a clutch when you need it is really really bad.
Engine braking is good practice. Putting aside the cleverness of modern ECUs, most footbrakes fade with use as they heat up. Yes, even disc brakes; they're a heap better than drum, but they can still overheat very rapidly.
If you're coming down a very long, steep hill and you're not engine braking, your brakes will be much less effective by the time you reach the bottom.
Brakes are a safety device, not a speed control tool. You brake only when required. Your accelerator pedal and engine braking is what you use to control your vehicle's speed. If you need to use your brakes other than to come to a stop, you're pushing your car too damned hard, or you're too damned close to the guy in front of you. Back off.
An American Road & Track issue from many years ago (and I'm damned if I can recall which one) had a long article on the results of some fuel economy studies conducted by BMW.
The findings seemed to show that driving style was more important than overall speed.
The tips, in general, were:
- Keep your speed constant; fluctuations up and down are bad. - Accelerate to your target speed quickly. Spending time slowly accelerating up to it wastes fuel. - Be in the highest gear feasible for your engine type and road speed. - 75% throttle for acceleration, conditions permitting. - Keep your revs low, and change gears often to keep them low. That said, know your torque curve, and use it; if you have a small 4 cylinder, trying to accelerate at 1000 revs is futile.
Agreed. As residents of a Commonwealth nation, my family has owned several four-wheel-drives of a different sort: Land Rover. Not new ones, old ones. Quite common in countries that didn't have ready supplies of the ubiquitous Jeep immediately after WWII.
The first 1948 Series I Land Rovers were made from a lightweight alloy of aluminium and magnesium, due to post-war steel shortages. They don't corrode readily, and my family had one of these Series I machines for a dozen or more years. Had a little straight four engine, long stroke. Gobs of torque via very low gearing indeed.
We've got a Series III right now, which has been retrofitted with an Australian knock-off of an American small-block V8. It's not doing so well, engine-wise, but the body just keeps going.
It's machines like this that we need to keep around. Strong, high-wheelbase, utilitarian, unkillable... and useful. Drive a small, efficient vehicle every day, by all means. I encourage it. Let's just not lose the really useful vehicles, because you never known when you'll need them.
No, not correct. Because I was covering a variety of different organisations, I was trying to locate a generic enough term. Of course I can't speak for all university or student societies in Australia, but I can can tell you that the UTas Anime Society obtains written permission to screen all material before we do. We have an excellent relationship with our local distributors and copyright holders. They're very forward-thinking and only too happy to increase their audience base.
Heck, they're even cool enough to ship us free stuff for competitions and the like.
That would probably be due to the differences in legal systems between the two countries. Litigation here is generally a last recourse, not a first, and having more money is no guarantee that you'll win.
We also have a proud tradition of the judiciary overturning legislation, or neutering it in execution.
No, genuinely interested. Modchipping old XBOXen has become de riguer as a media centre machine for cash-strapped student organisations that run screenings of various materials.
Slashdot Mirror
That's incorrect. They do offer the subscription in-app. It goes through the App Store, and Apple takes 30% if you choose to do it that way.
http://recode.net/2014/03/27/m...
Paid in full.
Also here.
Pretty early on in the piece to be slashdotted. Pulled for some reason?
But you can't. IANAL, but any contract that says "you agree to any changes in the future" is illegal and non-binding.
This is why WoW's Terms and Conditions are continually popping up for you to agree to -- every time they make a change, you have to reagree.
I think you'll find that's any Australian bank.
Actually, any bank at all. Um. ...is there a trend we're missing here?
I think you'll find that's a bonus.
Unless you're doing something really wrong, normal shifting of gears shouldn't cause any undue wear at all.
At any rate, I'd rather replace the gearbox, if it meant greater safety.
I live in Tasmania, Australia. Mountains are city driving.
I was always taught to drive as if the car could fail at any second. Because, you know, it could. Modern mechanicals aside, I'm directing the momentum of a 1.2 metric tonne lump of steel at speeds above 100kpmh. Treating that with anything less than utter respect leads to disaster.
Excuse me while I see to my own safety, and that of those around me.
Of course. I'm talking primarily about brake fade due to over-braking over the course of a drive. A hot day, a long hill, etc.
Is this some curious American-state-of-Oklahoma thing that I am unaware of...?
Caveat: I have a manual, and will never own an auto.
tylernt covers the "full throttle" component of this in another reply to your post.
I'm an Australian, and the son of an engineer who restores old vehicles for a living. We have British, Italian and Japanese vehicles. We have never owned an American vehicle.
The BMW data was almost certainly collected for their vehicles, which almost uniformly (at the time of the study) used straight 4 or straight 6 engines. 75% throttle would have been a rough figure arrived at for their own machines, I would imagine.
It is patently obvious that applying more throttle increases the amount of fuel used per second. However, the amount of fuel used is not a direct 1:1 to your acceleration.
The trick here is not that you use less fuel to reach your desired speed by accelerating harder. That's nonsense, and an incorrect understanding of the problem. Accelerating harder may well use more fuel to reach your desired speed. The trick is in how much time your spend at you desired speed, not accelerating.
If you do the calculus on this, you'll note that with the rapid acceleration model, you spend a far greater time at your desired target speed over the course of your journey. While at that speed, you are not accelerating. You will use more fuel accelerating quickly than accelerating slowly, per unit of time. However, your overall time spent not accelerating but simply maintaining speed more than compensates.
Did you do this with a high torque engine? I can't see this technique working so well with a low torque engine. :)
I assume that if you do have brakes of that sort, you'll be using them correctly. :) You'd probably have a fair to reasonable working knowledge of cars and car driving if you had a machine that used carbon ceramic discs!
To be fair, though, that type of brake can still overheat and shatter.
It's counter-intuitive, but relatively rapid acceleration is far better than slow acceleration.
A long, slow acceleration up to a target speed will use more fuel than a rapid acceleration up to a target speed. This is regardless of the vehicle's horsepower or torque.
Downhill coasting I've covered in other posts in this thread. Suffice it to say that brakes are a safety feature that you don't to have missing in an emergency.
Foolish. All engines are designed to brake.
Brakes are a safety device; you need them for keeping the car stationary, bringing it to a stop from low speeds, to prevent emergency situations from occurring, and for use in an emergency situation itself.
You save them; you don't use them. If you use your brakes as a matter of course, to control your speed, then you won't have them when you need them, due to heat build-up. No, disc brakes won't save you - they're better than drum, but they still heat up and loose effectiveness. No, ABS won't save you, either. It still has nothing to play with if your brakes have heated up.
Which would you rather: a bit of fuel economy (dubious anyway), or a large funeral bill?
Holding in your clutch a lot will stuff your throw-out race. That's really bad, because that'll lead to a clutch that you can't engage or disengage. Not having a clutch when you need it is really really bad.
Engine braking is good practice. Putting aside the cleverness of modern ECUs, most footbrakes fade with use as they heat up. Yes, even disc brakes; they're a heap better than drum, but they can still overheat very rapidly.
If you're coming down a very long, steep hill and you're not engine braking, your brakes will be much less effective by the time you reach the bottom.
Brakes are a safety device, not a speed control tool. You brake only when required. Your accelerator pedal and engine braking is what you use to control your vehicle's speed. If you need to use your brakes other than to come to a stop, you're pushing your car too damned hard, or you're too damned close to the guy in front of you. Back off.
An American Road & Track issue from many years ago (and I'm damned if I can recall which one) had a long article on the results of some fuel economy studies conducted by BMW.
The findings seemed to show that driving style was more important than overall speed.
The tips, in general, were:
- Keep your speed constant; fluctuations up and down are bad.
- Accelerate to your target speed quickly. Spending time slowly accelerating up to it wastes fuel.
- Be in the highest gear feasible for your engine type and road speed.
- 75% throttle for acceleration, conditions permitting.
- Keep your revs low, and change gears often to keep them low. That said, know your torque curve, and use it; if you have a small 4 cylinder, trying to accelerate at 1000 revs is futile.
Agreed. As residents of a Commonwealth nation, my family has owned several four-wheel-drives of a different sort: Land Rover. Not new ones, old ones. Quite common in countries that didn't have ready supplies of the ubiquitous Jeep immediately after WWII.
The first 1948 Series I Land Rovers were made from a lightweight alloy of aluminium and magnesium, due to post-war steel shortages. They don't corrode readily, and my family had one of these Series I machines for a dozen or more years. Had a little straight four engine, long stroke. Gobs of torque via very low gearing indeed.
We've got a Series III right now, which has been retrofitted with an Australian knock-off of an American small-block V8. It's not doing so well, engine-wise, but the body just keeps going.
It's machines like this that we need to keep around. Strong, high-wheelbase, utilitarian, unkillable... and useful. Drive a small, efficient vehicle every day, by all means. I encourage it. Let's just not lose the really useful vehicles, because you never known when you'll need them.
I think it will be demonstrated that the huge majority of people who want the iPhone can't get one yet, because it's not available in their country.
I want one, but Australia has no iPhone carrier. I could get an unlocked one, but I want visual voicemail, a decent data plan, etc.
No, not correct. Because I was covering a variety of different organisations, I was trying to locate a generic enough term. Of course I can't speak for all university or student societies in Australia, but I can can tell you that the UTas Anime Society obtains written permission to screen all material before we do. We have an excellent relationship with our local distributors and copyright holders. They're very forward-thinking and only too happy to increase their audience base.
Heck, they're even cool enough to ship us free stuff for competitions and the like.
That would probably be due to the differences in legal systems between the two countries. Litigation here is generally a last recourse, not a first, and having more money is no guarantee that you'll win.
We also have a proud tradition of the judiciary overturning legislation, or neutering it in execution.
No, genuinely interested. Modchipping old XBOXen has become de riguer as a media centre machine for cash-strapped student organisations that run screenings of various materials.
Not that I'm in any way in favour of the act, of course. I think any device you own should be able to be modified in any way you see fit.