Engine Braking
Discussion
Fairly simple one but I'm sure this will show divided opinion.
Is engine breaking something that (a) you should do in any modern car? (with the theory being that brakes used to be considerably less able and hence you needed the engine to help slow the car) and then (b) something that you should do with a performance car like a Tuscan?
Does this reduce the life of the engine, put additional stress on it that it doesn't need, etc?
I guess it is cheaper to get new brakes rather than a new engine, but just wondered if anyone has visited this before?
Is engine breaking something that (a) you should do in any modern car? (with the theory being that brakes used to be considerably less able and hence you needed the engine to help slow the car) and then (b) something that you should do with a performance car like a Tuscan?
Does this reduce the life of the engine, put additional stress on it that it doesn't need, etc?
I guess it is cheaper to get new brakes rather than a new engine, but just wondered if anyone has visited this before?
Engine to go, brakes to slow
Says it all really
If you use engine braking you *can* risk over revving the engine which cna in turn lead to valves and pistons coming together - which is "not a good thing"
I would use the brakes to stop the car, they are well up to the job after all, and as you say, brake pads are cheaper than valves!
MB.
Says it all really
If you use engine braking you *can* risk over revving the engine which cna in turn lead to valves and pistons coming together - which is "not a good thing"
I would use the brakes to stop the car, they are well up to the job after all, and as you say, brake pads are cheaper than valves!
MB.
Fairly simple one but I'm sure this will show divided opinion.
Is engine breaking something that (a) you should do in any modern car? (with the theory being that brakes used to be considerably less able and hence you needed the engine to help slow the car) and then (b) something that you should do with a performance car like a Tuscan?
Does this reduce the life of the engine, put additional stress on it that it doesn't need, etc?
I guess it is cheaper to get new brakes rather than a new engine, but just wondered if anyone has visited this before?
Engine braking is a big no-no in a rear wheel drive car, especially one with a big torquey engine like a TVR. It reduces the car's stability - how much depends on how much braking is applied of course, but it can very easily cause a spin and is one of the more popular ways of going off at a track day.
Like the man says, engine to go, brakes to stop.
Cheers,
Peter Humphries (and a green V8S)
quote : Is engine *breaking* something that (a) you should do in any modern car?
Looking at the forum and the topic I was expecting something else, but I use heel and toe and engine braking all the time, it's ok as long as you don't make a hash of the change and you brake in a straight line - the only times I've locked wheels is when 've ballsed up on the shift. The other thing I do though is not to change down at high revs, going to the next gear lower as the revs get down to maybe 2k/2.5k so there's no chance of buzzing the engine, and the wheels don't lock. incidently on this topic, changing down through the box to a lower gear reduces the chance of the wheels locking and engine stalling. in a high gear it's relatively easy for the wheels to drive the engine so if you lock the rear wheels the engine stalls, in a lower gear it's more difficult for that to occur. Also out on the road it's a good idea to not knock the car out of gear and coast to a junction since if your car hasn't got an LSD then you can lock one wheel if in an emergency stop situation - staying in gear reduces this effect.
:editedtohighlighttheunusualspellingforatuscanthread:
>> Edited by joospeed on Friday 22 November 10:20
Looking at the forum and the topic I was expecting something else, but I use heel and toe and engine braking all the time, it's ok as long as you don't make a hash of the change and you brake in a straight line - the only times I've locked wheels is when 've ballsed up on the shift. The other thing I do though is not to change down at high revs, going to the next gear lower as the revs get down to maybe 2k/2.5k so there's no chance of buzzing the engine, and the wheels don't lock. incidently on this topic, changing down through the box to a lower gear reduces the chance of the wheels locking and engine stalling. in a high gear it's relatively easy for the wheels to drive the engine so if you lock the rear wheels the engine stalls, in a lower gear it's more difficult for that to occur. Also out on the road it's a good idea to not knock the car out of gear and coast to a junction since if your car hasn't got an LSD then you can lock one wheel if in an emergency stop situation - staying in gear reduces this effect.
:editedtohighlighttheunusualspellingforatuscanthread:
>> Edited by joospeed on Friday 22 November 10:20
I think it really depends on what you mean by engine breaking?!!
Progressing swiftly, dropping gears - NO it can make the back end very unstable.
(Note if you are are good at heal and toe braking, you are NOT then engine breaking as you are then matching revs to gear selected)
Crusing up to a junction, foot of throttle letting the engine slow you down - Shouldn't hurt. But brakes designed to slow you down and are still cheaper to replace than drivetrain/clutches.
This is how my father was taught to drive many years ago and is what he would consider to be engine brakeing
(he also drops a gear, front drive 1.0L metro though)
Engine braking was taught all those years ago, because 'most' average cars had crap brakes. Not because it was a good technique. You would not have done it in a ferrari or AC cobra or E-type.
B
Progressing swiftly, dropping gears - NO it can make the back end very unstable.
(Note if you are are good at heal and toe braking, you are NOT then engine breaking as you are then matching revs to gear selected)
Crusing up to a junction, foot of throttle letting the engine slow you down - Shouldn't hurt. But brakes designed to slow you down and are still cheaper to replace than drivetrain/clutches.
This is how my father was taught to drive many years ago and is what he would consider to be engine brakeing
(he also drops a gear, front drive 1.0L metro though)
Engine braking was taught all those years ago, because 'most' average cars had crap brakes. Not because it was a good technique. You would not have done it in a ferrari or AC cobra or E-type.
B
The IAM would advise not using engine braking....on the downchange. What this really means is changing down and letting the clutch up whilst slowing - this means the clutch is acting as a brake.
Brake pads are cheaper.
I don't think there's anything wrong in allowing the engine to slow you by simply coming off the gas. Experts may say different?
Peter (GreenV8S) is exactly right about downchanging whilst braking too.
The IAM advise not overlapping braking and downchanging...although Roadcraft does admit that there may be occasions where this could be beneficial...at low speed, I think.
Personally - I don't overlap downchange and braking unless I heel and toe. H&T does save time on the track. On the road I've never found it necessary...but it is good fun and makes a great sound so what the hell?
There are a few good threads on this topic that might be worth hunting out. Words from Mapcop (Class 1 Police Driver) and also Peter Humphries (GreenV8S) and Steve Heath who are all expert drivers.
Brake pads are cheaper.
I don't think there's anything wrong in allowing the engine to slow you by simply coming off the gas. Experts may say different?
Peter (GreenV8S) is exactly right about downchanging whilst braking too.
The IAM advise not overlapping braking and downchanging...although Roadcraft does admit that there may be occasions where this could be beneficial...at low speed, I think.
Personally - I don't overlap downchange and braking unless I heel and toe. H&T does save time on the track. On the road I've never found it necessary...but it is good fun and makes a great sound so what the hell?
There are a few good threads on this topic that might be worth hunting out. Words from Mapcop (Class 1 Police Driver) and also Peter Humphries (GreenV8S) and Steve Heath who are all expert drivers.
joospeed said:
Looking at the forum and the topic I was expecting something else, but I use heel and toe and engine braking all the time, it's ok as long as you don't make a hash of the change and you brake in a straight line - ....
Master Jools,
I would have thought the very purpose of heel and toeigng was to synchronise the engine revs with the wheels revs, thus *avoiding* engine breaking.
rthierry said:
joospeed said:
Looking at the forum and the topic I was expecting something else, but I use heel and toe and engine braking all the time, it's ok as long as you don't make a hash of the change and you brake in a straight line - ....
Master Jools,
I would have thought the very purpose of heel and toeigng was to synchronise the engine revs with the wheels revs, thus *avoiding* engine breaking.
There are two types of engine braking. First one is where you engage the clutch while the engine is going too slowly for the gear you're in. This produces a large amount of engine braking and destabilizes the car a lot - just say no. If you match the engine revs (and heel-n-toe is a popular way to do this during down-shifts) you avoid this effect.
Second one is where you simply have a trailing throttle with the clutch engaged and are decelerating using the engine resistance instead of / as well as the brakes. This has a much less pronounced effect and is OK as long as you are aware that it does still reduce the stability and can be enough to upset the car. For example if you find you're going into a corner too fast on a wet road and lift off the throttle, this can be enough to provoke a tail slide and put you into the scenery when the same amount of decelleration via the brakes would be no trouble. Lifting off is often the wrong answer. Keeping the power on or a dab on the brakes are far safer options.
So although engine braking (the second sort) often won't do any harm, it a bad habit to get in to with rwd cars. The first sort, of course, is much more dangerous and should be avoided at all costs.
Hope this makes sense,
Peter Humphries (and a green V8S)
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