Braking distances 40 years out of date?
Discussion
Why does the Highway Code/"Safety camera Partnerships" etc still pubicise braking distances that are about 40 years out of date.
There have been huge reductions in a cars ability to stop over this time, better tyres, brakes, suspension etc even if we are still driving on the same (rather worn out) tarmac.
Yes I know about the thinking distance which will not change that is not the point I am making.
Is it politically incorrect for these departments to accept that even the cheapest car today has substantially better sopping ability than a high performance car from the 1960's.
PS I may be wrong about the 40 years, I only started driving in 1970 and maybe the figures were arrived at in the 1950's using a sidevalve Ford with cable brakes!
There have been huge reductions in a cars ability to stop over this time, better tyres, brakes, suspension etc even if we are still driving on the same (rather worn out) tarmac.
Yes I know about the thinking distance which will not change that is not the point I am making.
Is it politically incorrect for these departments to accept that even the cheapest car today has substantially better sopping ability than a high performance car from the 1960's.
PS I may be wrong about the 40 years, I only started driving in 1970 and maybe the figures were arrived at in the 1950's using a sidevalve Ford with cable brakes!
Ive collated data on multiple occasions using data logging, with various cars, your average numpty car without ABS is just about spot on to the highway code fugures. Yes some high performance cars are better by quite a long way but many many cars are quite franky not.
One new technology that does definately decrease stopping distances for Mr Average driver who still does'nt know how to operate an ABS equipped car, is brake assist, its quite staggering just how good it is. Alas it's only fitted to largeer modern high spec cars, though does appear on some repmobiles like the Mondeo.
The reaction times are correct, but if you'd seen the data that Toyota did a few years ago that found a vast percentage of drivers dont brake when they could have done. Panic reactions are far more of a worry to me than the HWC data.
One new technology that does definately decrease stopping distances for Mr Average driver who still does'nt know how to operate an ABS equipped car, is brake assist, its quite staggering just how good it is. Alas it's only fitted to largeer modern high spec cars, though does appear on some repmobiles like the Mondeo.
The reaction times are correct, but if you'd seen the data that Toyota did a few years ago that found a vast percentage of drivers dont brake when they could have done. Panic reactions are far more of a worry to me than the HWC data.
cptsideways said:
Ive collated data on multiple occasions using data logging, with various cars, your average numpty car without ABS is just about spot on to the highway code fugures. Yes some high performance cars are better by quite a long way but many many cars are quite franky not.
One new technology that does definately decrease stopping distances for Mr Average driver who still does'nt know how to operate an ABS equipped car, is brake assist, its quite staggering just how good it is. Alas it's only fitted to largeer modern high spec cars, though does appear on some repmobiles like the Mondeo.
The reaction times are correct, but if you'd seen the data that Toyota did a few years ago that found a vast percentage of drivers dont brake when they could have done. Panic reactions are far more of a worry to me than the HWC data.
One new technology that does definately decrease stopping distances for Mr Average driver who still does'nt know how to operate an ABS equipped car, is brake assist, its quite staggering just how good it is. Alas it's only fitted to largeer modern high spec cars, though does appear on some repmobiles like the Mondeo.
The reaction times are correct, but if you'd seen the data that Toyota did a few years ago that found a vast percentage of drivers dont brake when they could have done. Panic reactions are far more of a worry to me than the HWC data.
I hesitate to ask this, but err, how do you operate an ABS equipped car?
cptsideways said:
One new technology that does definately decrease stopping distances for Mr Average driver who still does'nt know how to operate an ABS equipped car, is brake assist, its quite staggering just how good it is. Alas it's only fitted to largeer modern high spec cars, though does appear on some repmobiles like the Mondeo.
Not just larger cars, my Smartie has it as standard and bloody hell it does stop in a remarkably short distance.
I was cut up by a car and applied 'normal' emergency braking shove to the brake pedal at 30mph.
Weird - one second moving, the next stopped with no drama. Though no doubt if there had been a numpty behind I'd have been rear-ended.
Didnt think ABS would stop you much/if any quicker than full lockup. It does enable braking and some stearing which full lockup does not.
Tyres only have a certain level of grip, they use up their 'points' cornering and or braking but cant exceed their grip level points. if you are stearing you are already using up some of the grip points. hence brake in a straight line.
Tyres only have a certain level of grip, they use up their 'points' cornering and or braking but cant exceed their grip level points. if you are stearing you are already using up some of the grip points. hence brake in a straight line.
You stop significantly quicker if you do not lock up and I guess it will depend on how good the ABS system in question is whether it will stop you quicker or not. Some of the older ones were quite crude but I suspect a modern system would stop you significantly quicker than locking up.
Rob
Rob
Modern ABS outperforms manual breaking in the real world as it can optimise the breaking on each wheel for the level of grip at that split second, something two feet and one pedal can not do.
The biggest "issue" with ABS and to be fair non-abs cars to a degree is that people just don't break hard enough. On an ABS car you have to stand on your brakes, attempt to the push the pedal through floor, do not release pedal pressure until the car is stopped. The average driver will not apply enough pressure to the brake pedal (ABS or otherwise) or will release it when the feel the ABS "pulsing" the brake pedal. That is why brake assist as such good real world results as it applies maxium "pressure" throughout the stopping period.
Emergency braking is violent, seat belts should lock up, your passenger should be bracing themselves. It should be compulsary to do an emergency stop from 70 and not the 20 that you currently do. If you haven't done it, you should try, it isn't hairy but you need to realise what full braking is all about.
The biggest "issue" with ABS and to be fair non-abs cars to a degree is that people just don't break hard enough. On an ABS car you have to stand on your brakes, attempt to the push the pedal through floor, do not release pedal pressure until the car is stopped. The average driver will not apply enough pressure to the brake pedal (ABS or otherwise) or will release it when the feel the ABS "pulsing" the brake pedal. That is why brake assist as such good real world results as it applies maxium "pressure" throughout the stopping period.
Emergency braking is violent, seat belts should lock up, your passenger should be bracing themselves. It should be compulsary to do an emergency stop from 70 and not the 20 that you currently do. If you haven't done it, you should try, it isn't hairy but you need to realise what full braking is all about.
TVR keith said:
Why does the Highway Code/"Safety camera Partnerships" etc still pubicise braking distances that are about 40 years out of date.
Because they can't cope with change.
I've got some real world numbers in front of me
from Road and Track magazine. Over 100 different
cars sampled from Porsches to Ford.
Stopping distances from 60 mph range from 107 feet to
157 feet.
Stopping distances from 80 mph range from 184 feet to
285 feet.
This makes the claim of 310 feet from 70 mph by the
highway code look a bit silly.
Oh well, what's new - unrealistic Government numbers.
I think I'll investigate the Pope's religious affiliation next.
herewego said:
cptsideways said:
One new technology that does definately decrease stopping distances for Mr Average driver who still does'nt know how to operate an ABS equipped car, is brake assist, its quite staggering just how good it is. Alas it's only fitted to largeer modern high spec cars, though does appear on some repmobiles like the Mondeo.
I hesitate to ask this, but err, how do you operate an ABS equipped car?
Don't lift off at all, maintain full hard brake pressure, "most" drivers release the brake when they sense the pulsing effect through the pedal further increasing the stopping distance. This is why Brake Assist was invented.
Note: Brake assist cars actually sense the speed at which you apply the pedal Ie initial travel speed not pressure. The system can be set off by simply tapping the pedal. It remains at full brake pressure until the pedal is released.
Zod said:
cptsideways said:
Ive collated data on multiple occasions using data logging, with various cars, your average numpty car without ABS is just about spot on to the highway code fugures.
Are there any cars now on the market without ABS?All new cars sold have to have ABS fitted as standard as they are so effective.
The Hitman said:
Zod said:
cptsideways said:
Ive collated data on multiple occasions using data logging, with various cars, your average numpty car without ABS is just about spot on to the highway code fugures.
Are there any cars now on the market without ABS?All new cars sold have to have ABS fitted as standard as they are so effective.
No they don't.
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