You go tell Michael Shumacher hes been an idiot for using engine braking then

F1 cars have some of the best brakes in the world - yet the drivers still use engine braking constantly. Perhaps they are all idiots who need to take an IAM test? Perhaps they need to be taught by their local bobby?

im sorry i thought we were talking about driving on uk roads not racing round a track?!?

2 completly different things a bit silly to compare them to be honest.

and from what ive seen/heard schumacher doesnt drive like a ***** when he's of the track so theres a good chance he could be lazy and not change down

You go tell Michael Shumacher hes been an idiot for using engine braking then

F1 cars have some of the best brakes in the world - yet the drivers still use engine braking constantly. Perhaps they are all idiots who need to take an IAM test? Perhaps they need to be taught by their local bobby?

im sorry i thought we were talking about driving on uk roads not racing round a track?!?

2 completly different things a bit silly to compare them to be honest.

and from what ive seen/heard schumacher doesnt drive like a ***** when he's of the track so theres a good chance he could be lazy and not change down

If you think that a competition driver is an entirely different driver and switchs from "instinctive" driveing to rigid code following for road driving you're very wrong. Certainly my pace is lower on the road and I dont "use the whole road" You wont catch me using a scandinavian flick to enter sainsburys car park.

But the same brain is controlling the same reactions what feels right on the track feels right on the road. I dont doubt that sometimes he wont bother changeing down, I certainly dont every time, but I also dont doubt that there will be times when hes lazy and when hes not thinking about the act of driving when he will be changeing down through the gears on instinct.

If your race responses have to be thought about they wont happen fast enough the only way actions become natural reactions is through putting them into practise.

Jeezus I thought we had buried this one for good then someonecomes along and resuscitates it!

Pitting road driving techniques against competition techniques is quite simply pointless. The two briefs are so different as to be almost without common ground.

Competition driving, the ojective being to cover ground at the fastest possible rate. The expected "incident" rate in driving in a race would be perhaps 1 incident per 10 miles for you average competitive clubman racer. By incident, I mean that corner where you lost it a bit then recovered it or got that entry speed a bit too high and had to run a bit wide to scrub off the speed. The point is that these techniques are used at the very limit of what the car can do in order to cover ground at maximum pace. The techniques compromise other aspects of the car / driver control system to achieve this. A similar "incident" on the road will often result in an accident as you are genrally required to keep the plot out of the oncoming traffic and not bounce it off the verges.

The system of car control advocated by RoSPA or the IAM is optimised to cover the ground safely and effectively. Here an "incident" may be expected pehaps once in every 100,000 miles if you are not paying attention. The system minimises the possibility of error in the car / driver control system. The driver is not expected to work beyond the cars limits of adhesion and not to work the car to its mechanical limits with respect to the braking system.

This last bit is the key of course. Engine braking is a system adopted in competition for only one reason. Brake heat and wear management. The race driver is required to utilise engine braking which may account for up to 15% of the cars retardation as that means the driver will have his brakes last longer throught the session or retain more stopping power by slightly reducing heat build up. Ask any racer what he really wants up to and at the turn in point and he will tell you that he wants absolutely maximum stopping power from all four tyres and to be in the right gear at the turn in point.

The effect of engine braking is to introduce some undesirable variables, which is why even for a competition driver it's use causes compromise. For a start, given a rear wheel drive car, there is the distinct possibility of locking up the wheels as I have done on dry tarmac more than once. Bigger engines with heavier internals are worse due to the inertia of the rotating / riciprocating masses. The engine braking also causes the braking force being transmitted to the road to be variable on the driven wheels. Thus at any given time, the driven wheels may be subject to locking up when the non driven wheels are not braking at maximum force. We need to remember here that the brake bias of a competition car may be set up for engine braking whereas a road car will almost definately not be.

Bottom line is that engine braking is undesirable but necesary for racing to preserve brakes, or in the case of gravel / mud racing to keep the rear end mobile, but totally unnecesary for road driving. In road driving, the variability of the force delivered by engine braking can introduce instability.

Personally, I use what is ok for the road situation. This may include engine braking (the IAM / RoSPA system calls for its use in some circumstances), trail braking (the MR2 just loves this to nail an apex), brake gear overlap, opposite lock, cadence braking, handbrake assisted steering, changing down sequentially and all manner of other little tricks of the trade. More importantly, I use the system of car control as advocated by RoSPA and the IAM to ensure that I dont NEED to utilise techniques at the very edge of car control to rescue me from a situation that I should never have got into. And I dont drive like a granny, most of my mates reckoning I am the quickest driver they ever passenger with.

Chris

But if you are coasting down hill in neutral you don't have engine brakeing slowing your car down, do will actually gain speed and therfore negate any losses from fueling to keep the engine at tickover.

I tried this theory out on a nice long downhill (on a private road) and the car was reporting much higher MPG figures from the coast when compared to the leave it in top and go down the hill.

Better than the "not actually using any fuel (---.- mpg)" reports that my Octy normally gives on the over-run in gear?

Better than the "not actually using any fuel (---.- mpg)" reports that my Octy normally gives on the over-run in gear?

Yep have to agree Ken - I used to think that coasting in neutral was the most fuel efficient, but found that leaving it in gear and letting the engine compression get the car down the hill used even less fuel. The difference is probably minimal in real world terms, but using engine braking to maintain current speed means that you're in the right gear should you need a squirt of power in a hurry too

Chris

Actually, should just add that I've had the spot mode report anything up to about 750.0 or so on immediate lift off, before it goes to ---.- .

Yep have to agree Ken - I used to think that coasting in neutral was the most fuel efficient, but found that leaving it in gear and letting the engine compression get the car down the hill used even less fuel.

That's because fuel injection systems have a fuel cut-off on a trailing throttle, whereas coasting requires fuel to keep the engine ticking over.

Not read the thread but sorry if it's been mentioned, engine braking exerts reverse thrust on clutch, gearbox and drivetrain components and should be avoided from a mechanical point of view.

So what do you non down shifters do when you come across this sign?

http://www.freefoto.com/images_d/41/08/41_08_85_thumb.jpg

So what do you non down shifters do when you come across this sign?

http://www.freefoto.com/images_d/41/08/41_08_85_thumb.jpg

It is apparent from your comments and general opinion that you have absolutely no understanding of the requirements of the RoSPA / IAM drive. Of coure engine braking is used in specific circumstances, but I refer you to my earlier post, the technique is used by good drivers where appropriate and not by default.

You wont see IAM / RoSPA instructors telling you the best way to race, so why would you presume to be qualified to advise the best way to drive on the road. That you can sling a car down a stage, does not indicate that you will be a good road driver. Further, your comments on situations where you would find yourself in an emergency situation where changing down through the gears will have helped you would indicate that you are possibly not a good road driver, merely one who relies on marginal car control (and it the gear you are in is that critical in the situation the control is marginal) to compensate for your lack of road driving skills, namely observation and planning.

Chris

It is apparent from your comments and general opinion that you have absolutely no understanding of the requirements of the RoSPA / IAM drive. Of coure engine braking is used in specific circumstances, but I refer you to my earlier post, the technique is used by good drivers where appropriate and not by default.

I agree with that ENTIRELY. Feel and adaptability are ABSOLUTELY vital' date=' a knowledge of what you can do to effect a car in different situations helps you to select what feels right at that time.

I will often say the fastest way to stop a car is to put it sideways, but that doesnt mean I use that idea every time I want to stop - or even any appreciable percentage of the number of times I stop. Equally people may say dont brake and steer as a hard and fast rule, which of course might be good advice, but I left foot brake and that I consider safe, but I dont left foot brake every corner, and some times I left foot brake sometimes I scandinavian flick sometimes I slow down and hand brake, its all feel, and theres so many different ways to change the physics of whats happened to your car.

[b']But when it comes changeing down through your gears I argue strongly against it being pointless or a bad idea, but it doesnt mean I apply it every time hard and fast.[/b]

Whos quoting hard and fast rules here?, theres a poll here some people are saying "no" they dont change down through gears when slowing down, Then theres a "yes" camp, I say anyone who doesnt ever change down when slowing down - the "no" camp, are at times sacrificing a LOT of potential control of their car. I work with what feels most appropriate for the situation. Mottos like "gears are for go brakes are for slow" fall in the same bin of nonsense as "Speed Kills. Kill Your Speed

Whos quoting hard and fast rules here?, theres a poll here some people are saying "no" they dont change down through gears when slowing down, Then theres a "yes" camp, I say anyone who doesnt ever change down when slowing down - the "no" camp, are at times sacrificing a LOT of potential control of their car. I work with what feels most appropriate for the situation. Mottos like "gears are for go brakes are for slow" fall in the same bin of nonsense as "Speed Kills. Kill Your Speed

Those have got to be the two longest posts I've ever seen on here :eek:

Steve

Is this still going ? :?

So what do you non down shifters do when you come across this sign?

http://www.freefoto.com/images_d/41/08/41_08_85_thumb.jpg

That's a different question; we're saying "do not change down in order to brake the car", not "do not change down to use engine braking to ease maintaining a steady speed downhill". If the difference between road and competition (including 'closed road as competition) driving is getting too much for you, you can always stop claiming that the competion method is applicable to open road situations!

Those have got to be the two longest posts I've ever seen on here :eek:

Steve

Even worse than some of mine! :eek:

That's a different question; we're saying "do not change down in order to brake the car", not "do not change down to use engine braking to ease maintaining a steady speed downhill". If the difference between road and competition (including 'closed road as competition) driving is getting too much for you, you can always stop claiming that the competion method is applicable to open road situations!

Although I didnt make it clear that response was in fact to the claims that engine braking kills gearboxes etc, Which I have never yet experienced, on or off road. Bad handling of gear changes will kill gearboxes in acceleration as well as engine braking.

Although I didnt make it clear that response was in fact to the claims that engine braking kills gearboxes etc, Which I have never yet experienced, on or off road. Bad handling of gear changes will kill gearboxes in acceleration as well as engine braking.

Still don't get your point. What you seem to be arguing for the most part is use of closed throttle downshifts to obtain an (IME fairly brutal) burst of extra deceleration on a level road, and then you introduce the case of downshifting at constant road speed, and increasing revs, in order to have engine braking available for a steep downhill.

Not a case of quoting hard and fast rules anywhere. Anyone who never uses engine braking would fall outside of the IAM / RoSPA camp. Fundamentally, brakes are for slowing the car down. Use of engine braking will assist in this under certain circumstances, but is not often essential for retaining control within the framework of a road drive in normal traffic. Further, used in isolation in some circumstnaces, the simple matter of not showing brake lights when reducing speed could be hazardous in itself. Like yourself, I full agree that the "speed kills" doctirine is rubbish, however, inappropriate speed kills would be just a bit too much for the great general public to interpret according to our masters. Having said all that, and having spent many years in one sort of driver training or another at advaned level, I have never heard the "speed kills" doctrine being spouted by any of these organisations. They are very down on inappropriate use of speed though, as I am sure you are.

Rally driving will enhance certain skills. Reading surfaces, predicting road camber changes, observing the road to work out the best course, considering the possible actions of spectators who for the most part are aware that you are there. Playing these requirements off against the cars behaviour. Working on the knife edge. Car control skills will be greatly enhanced by practicing all of this. However, when out on the road, there are factors to consider that no amount of rally experience will make any difference to. For a start, there is the ever present threat of other road users. What they randomly do will require skills that no amount of rally work will prepare you for. Sure a higher level of car control may help you avoid the collision, but the key thing on the road is to predict the situation. This takes long term observation and strategy. I am absolutely sure that rallying does not predispose one to being significantly better at predicting the interactions of other road users, simply because the hazard at race speeds is either there or not there, and very seldom, if ever, developing.

I have never raced in a rally but I have regularly driven at 10/10ths for fun. The rally driver, like the road driver, sets the risk level and uses the skills set to mitigate the risks. 100mph on snow without studded tyres, fast bikes in the wet, three figure speeds on small muddy rural roads. All been done for fun. I just love that risk feeling, but when there are other road users about I revert to road technique driving.

I personally am under absolutely no illusion at all of what it takes having had a go at driving a competition prepped car on farm tracks. This, I must confess, seemed a fair bit easier than going fast on a competition prepped bike in the wet or dry though. Although the car would sway about and get twitchy, it was relatively easy not to fall off of it as it had four wheels. I would liken any competition driving to working the car at its absolute limit. Here, the smallest of errors are potentially punished by the largest of penalties. The huge speed means that the driver only has the latitude of a small "window of control" in which to assert his / her will on the car. What you learn about feel does certainly carry over to the road, but whan other traffic is about, you are seldom if ever going to need to call on that last little bit of car control. If you need to, you have made an error of judgement.

Again, observation of some aspects, probably more geared to the physics of driving. Road driving incorporates the need to assess hazards that can be developing while you approach them. For this, yon need to think in terms of the build up to the situation, the contributary factors, the arrival of other road users and the rate at which they are travelling. Are these skills something that the rally driver needs to practice in racing? Anyone who regularly drives their car successfully close to the limit of its abilities will have better car control at lower speeds as they have more "headroom" in road situations.

I have lifted these examples from your previous post:

Do you find yourself in these sort of scenarios regularly? If so, you may well find your car control allows you to lose speed quicker than the average driver. However, what about the numpty behind you? I regularly teach people who come up to hazards too fast and they regualrly tell me there is enough time to stop. These people will regularly be hit from behind one they pass their test and selectively discard what I have taught them. It is nothing to do with car control and all about having time ot read and respond to the situation.

I agree with this in general. There are some issues with taking the speed for granted with some drivers though. They will someties be travelling at what they consider a sedate pace and will catch out a "normal" road user with the speed they approach at. This is the failing of the "normal" driver in some respects, but it does not count for much whose fault it is when the metal is bending.

I am not saying that a rally driver lacks observation and planning, but that a rally driver will have observation and planning geared to rally driving. This is different from road driving and as stated above, the nature and timescale of the hazards, and the required responses, are totally different to the requirements of general road driving. I stated this as your previously quoted "waht if" situations all appeared to be the ort of thing that would happen to a driver not really predicting the potential hazards and thus arriving a bit too fast, then having to rely on car control to get them out of the poop.

And therin lies the key fact. Yes the car control system is geared to slow down the driver. It absolutely has no place in on limit car control. There are some mightly strange concepts, the one I find most odd being the balance of the car. My idea of the car being balanced in a corner is when the front and rear wheels are closest to the same slip angle, achieved via use of whatever means are required to get the car "set up" for the corner. However, because of the nature of road driving and the timescales and circumstances of how a road hazard develops, you need to arrive slower than at "optimal track speed" to be able to assess the situation and respond to it. The idea of these drives is to get you moving at a speed that allows you to apply and almost "game of chess" like strategy to driving, giving plenty of time for sussing out fully all the possible hazards and your possible routes through or around them. It is gerared to get you approaching situations at a speed that gives other road users enough time to deal with your arrival into the situation.

I think that any form of high speed car control, be it rallying, fast road driving, circuit driving will appeal to many who take the art of driving more seriously than the average motorist. It will give the driver more confidence in their own abilities nd allow them to better know the physical limits of cars in genral. This must to some degree help them be safer road drivers if they use this knowledge sensibly.

Push pull steering is not the only permissable method of steering in advanced driving, hand over hand being acceptable where required. However, if you require it because your speed is too high for the situation, then there will be an issue with the examiner.

Road craft car handling is all about limited speed and forces. It is not aout race speeds and high forces. I would be the first to agree that the car control system is a dead loss once the speed in a corner goes to a point where grip is starting to become challenged. However, I would really like to hear a better method for road driving than use of limit point analysis.

Nice sentiment but really not practical in the real world. The driving intruction trade is generally suffering these last few years because the increasing standard of the driving test is putting people off driving. Mostly, they just cant afford enough lessons to reach the standard.

Roads are in use by drivers of all levels of competence, and yes, IAM / RoSPA is designed to make the driver operate the car at speeds where they will fit in. It is also designed to allow drivers to make safe and reasonable progress within the limits of their capabilities as road drivers.

For all the rhetoric, I challenge you to tell me a method of negotiating a given country lane that is any better and safer than the Roadcraft "Limit Point Analysis" method. If you can come up with it, I will use it.

Chris

[ontopic] Just because modern brakes are better than they once were doesn

Good grief man! I'm enjoying reading this thread and think it's a good discussion to be having, but is it really necessary to quote the whole of Chris' post?!

And I think you need to be a bit more articulate in the point you're trying to get across and stop being so 'wordy' :grumpy:

:rant:

Steve

Still don't get your point. What you seem to be arguing for the most part is use of closed throttle downshifts to obtain an (IME fairly brutal) burst of extra deceleration on a level road, and then you introduce the case of downshifting at constant road speed, and increasing revs, in order to have engine braking available for a steep downhill.

You seem quite mixed up there, lets seperate out your various ideas there.

1) Closed throttle down shifts for an extra burst of deccleration.

Degree of how closed the throttle is would be very up for debate, as would the brutality, in a situation where I would use that technique it would be "fed" in on the clutch, not necesarily raising the clutch the whole way, using it as a speed cushion, rather than a brutal form of stopping, balance between throttle , which gear, what speed etc would be completely tailored to the situation. a "brutal" action in such a scenario would be a guarantee of an accident.

2) Downshifting at constant road speed, and increasing revs, in order to have engine braking available for a steep downhill.

This is the one I would guess you are taking from the sign post?

I certainly would not suggest doing your slowing down just on gears in this situation, but engine braking will be applied and revs may increase to a degree whilst helping to hold speed down, without over depending on brakes.

Any body who says engine braking breaks gear boxes is surely not going to follow the sign and "keep in low gear" to help maintain speed. Even modern brakes can give up in road use at normal road speeds without any use of "gearbox breaking engine braking".

This is very consistant with my arguement in this thread that changeing down through the gears as you slow down is better than relying on brakes along and remaining in 5th gear till you come to a stop at a round about. - which I consider to be akin to coasting.

[ontopic] Just because modern brakes are better than they once were doesn

That last sentence is the key.

I've done a bit of competition driving , done a few advanced courses, and about 1.5 million road miles. When I started doing the advanced stuff, I found I was already doing most of the stuff, either intuitively or by a different name.....

The principles remain the same

Observation/information

Position / Course

Speed/Braking

Gear

Acceleration

It's how we drive. It's iterative but with obs/inf hanging over all the other phases.

Well nothing I've read so far - being lectured by two (no make that three) rather dogmatic individuals hasn't made me decide changing down is a bad thing, nor that it's the only way to drive. I think adaptability is probably the key.

If the two main protagonists would just listen to each other instead of looking for platforms for their own argument in each other's posts, I think they'd find they agree far more than they admit, although Chris has hinted at it in his last post.

Well nothing I've read so far - being lectured by two (no make that three) rather dogmatic individuals hasn't made me decide changing down is a bad thing, nor that it's the only way to drive. I think adaptability is probably the key.

If the two main protagonists would just listen to each other instead of looking for platforms for their own argument in each other's posts, I think they'd find they agree far more than they admit, although Chris has hinted at it in his last post.

I agree, Im still on the fence as to what to do with this one as there is no 100% answer. Both sides have experience and practise behind them.

I think the best question to pose at this point is, which method do you use and how many drivetrain parts have you had to replace?

I suppose that way we can see whats better for the car, and then practise what works better for us on the road when driving.

Ive been quite concious of how I have been slowing down and I have to admit, I have now changed slightly since reading some posts on this thread, and use "a bit of both". For example traffic lights that have been red for a while and Im approacing at 25~30mph then I change down, and brake - ready for them to go green. Also, if Im approaching a junction where I know I must stop and asses the traffic before moving off then I will use the brakes and not gears.

By looking at the arguements on both sides I think its going to be pretty hard to find one definative technique, and I would presume its just up to the driver to see or "feel" what works best for them.

Theres some really good arguements going on for and against and its a very good thread to read! Keep it coming!