using clutch to control car speed going down steep hill
Discussion
HustleRussell said:
Indeed the clutch doesn't care, and when was the last time anyone heard of a manual gearbox failing when used normally in a modern car?
I use engine braking a lot, it's smoother, more efficient and to me feels more mechanically sympathetic than riding the brakes.
As do I, engine braking is free, smoother for the occupants and doesn't wear your drive train or clutch out. I see the 'not lighting up the brake lights' as a good thing (which is a cause for motorway panic braking and flow compression)I use engine braking a lot, it's smoother, more efficient and to me feels more mechanically sympathetic than riding the brakes.
Consider this.
When you take your foot off the throttle, the ECU shuts down fuel to the engine, relying upon the vehicle monentum driving the gearbox to turn the engine. You use less fuel.
When you put your foot on the clutch, the engine is now disengaged from the transmission (freewheeling) and the ECU has to make sure fuel is being put in to keep the engine firing.
You use more fuel with the transmission engaged and off the throttle than you do when you use the clutch (disengage transmission)
Now I'm not saying use engine braking to excess - stopping the car is the job of the brakes, but if you want to loose a little speed, simply come off the throttle and it'll slow gently.
HustleRussell said:
Indeed the clutch doesn't care, and when was the last time anyone heard of a manual gearbox failing when used normally in a modern car?
I use engine braking a lot, it's smoother, more efficient and to me feels more mechanically sympathetic than riding the brakes.
Brother in laws 60k 320D manual lunched it's box. He was upset.I use engine braking a lot, it's smoother, more efficient and to me feels more mechanically sympathetic than riding the brakes.
My local hill. Lots of engine braking. Spirited driving using only brakes NOT advised (unless you like smoke).
http://stevecarter.com/random/TopToTails.mov (40mb)
http://stevecarter.com/random/TopToTails.mov (40mb)
gavsdavs said:
As do I, engine braking is free, smoother for the occupants and doesn't wear your drive train or clutch out. I see the 'not lighting up the brake lights' as a good thing (which is a cause for motorway panic braking and flow compression)
Consider this.
When you take your foot off the throttle, the ECU shuts down fuel to the engine, relying upon the vehicle monentum driving the gearbox to turn the engine. You use less fuel.
When you put your foot on the clutch, the engine is now disengaged from the transmission (freewheeling) and the ECU has to make sure fuel is being put in to keep the engine firing.
You use more fuel with the transmission engaged and off the throttle than you do when you use the clutch (disengage transmission)
Now I'm not saying use engine braking to excess - stopping the car is the job of the brakes, but if you want to loose a little speed, simply come off the throttle and it'll slow gently.
Yup. But always worth bearing in mind that with a rwd car you are applying braking only on the rear wheels, just like applying the handbrake. And when people abuse engine braking they can get a little bit of a surprise. Consider this.
When you take your foot off the throttle, the ECU shuts down fuel to the engine, relying upon the vehicle monentum driving the gearbox to turn the engine. You use less fuel.
When you put your foot on the clutch, the engine is now disengaged from the transmission (freewheeling) and the ECU has to make sure fuel is being put in to keep the engine firing.
You use more fuel with the transmission engaged and off the throttle than you do when you use the clutch (disengage transmission)
Now I'm not saying use engine braking to excess - stopping the car is the job of the brakes, but if you want to loose a little speed, simply come off the throttle and it'll slow gently.
Interestingly, it seems quite a common issue when people who have spent years ragging fwd cars switch to a performance RWD car and then wonder what the juddering f
k has just happened as they drift backwards over a roundabout. 
I recall watching a chap in a TVR coming down Fish Hill in the Cotswolds in the wet. He was holding a lower gear all the way down and using engine braking to help control speed, as all of is would in manuals, except when he got into the right hand bend towards the bottom off he went up the grass backwards.
DonkeyApple said:
Yup. But always worth bearing in mind that with a rwd car you are applying braking only on the rear wheels, just like applying the handbrake. And when people abuse engine braking they can get a little bit of a surprise.
Interestingly, it seems quite a common issue when people who have spent years ragging fwd cars switch to a performance RWD car and then wonder what the juddering fk has just happened as they drift backwards over a roundabout.
I recall watching a chap in a TVR coming down Fish Hill in the Cotswolds in the wet. He was holding a lower gear all the way down and using engine braking to help control speed, as all of is would in manuals, except when he got into the right hand bend towards the bottom off he went up the grass backwards.
I was talking about the "holding speed on a hill", or "gentle slowing on motorways" cases as opposed to slamming down gears, bringing out the clutch and locking the rears (generally trying to use the engine as forced braking system).Interestingly, it seems quite a common issue when people who have spent years ragging fwd cars switch to a performance RWD car and then wonder what the juddering f
k has just happened as they drift backwards over a roundabout. I recall watching a chap in a TVR coming down Fish Hill in the Cotswolds in the wet. He was holding a lower gear all the way down and using engine braking to help control speed, as all of is would in manuals, except when he got into the right hand bend towards the bottom off he went up the grass backwards.
It's built-in source of drag, not a parachute/anchor.
gavsdavs said:
I was talking about the "holding speed on a hill", or "gentle slowing on motorways" cases as opposed to slamming down gears, bringing out the clutch and locking the rears (generally trying to use the engine as forced braking system).
It's built-in source of drag, not a parachute/anchor.
Yes and agree but was just highlighting that you are still only braking with the driven wheels and on rwd cars I've seen them spin off doing exactly what we are talking about. It's built-in source of drag, not a parachute/anchor.
DonkeyApple said:
gavsdavs said:
I was talking about the "holding speed on a hill", or "gentle slowing on motorways" cases as opposed to slamming down gears, bringing out the clutch and locking the rears (generally trying to use the engine as forced braking system).
It's built-in source of drag, not a parachute/anchor.
Yes and agree but was just highlighting that you are still only braking with the driven wheels and on rwd cars I've seen them spin off doing exactly what we are talking about. It's built-in source of drag, not a parachute/anchor.
I'd say their transmission was knackered or one of their rear calipers was already binding. Engine braking can't lock tyres (assuming tarmac, not ice).
Slamming down gears and pulling out the clutch to lose speed is not the same thing, at all.
DonkeyApple said:
Yes and agree but was just highlighting that you are still only braking with the driven wheels and on rwd cars I've seen them spin off doing exactly what we are talking about.
then they are going to fast, have chosen the wrong gear and are nobs ....that's like saying brakes are bad because you lock them up by going to fast and stamping on them at the wrong time and to hard
Edited by Stickyfinger on Wednesday 29th July 17:02
SteveSteveson said:
Unless the OP is driving the Col du Turin with his car fully loaded that is not likely to happen. I only say this because the OP is a new driver so might think this is a genuine risk. At sensible speeds you are not going to overheat brakes on anything in the UK.
Maybe not in a decent car. It certainly can be done in a mk5 Fiesta in the countryside around Bath! Quite a surprising amount of smoke out of the front wheels and a very soft brake pedal. Bricks shat to say the least.budgie smuggler said:
Maybe not in a decent car. It certainly can be done in a mk5 Fiesta in the countryside around Bath! Quite a surprising amount of smoke out of the front wheels and a very soft brake pedal. Bricks shat to say the least.
Does not take a hill, just a daft foot attached to a daft driver I can vouch for that. The only upgrade I made to my first car was the brakes.
Surely anyone who loses control of their car due to inappropriate engine braking is driving like a tool. Lift-off oversteer must be the most likely mode. Of course using it too much in ice and snow is also asking for trouble.
Surely anyone who loses control of their car due to inappropriate engine braking is driving like a tool. Lift-off oversteer must be the most likely mode. Of course using it too much in ice and snow is also asking for trouble.
gavsdavs said:
DonkeyApple said:
gavsdavs said:
I was talking about the "holding speed on a hill", or "gentle slowing on motorways" cases as opposed to slamming down gears, bringing out the clutch and locking the rears (generally trying to use the engine as forced braking system).
It's built-in source of drag, not a parachute/anchor.
Yes and agree but was just highlighting that you are still only braking with the driven wheels and on rwd cars I've seen them spin off doing exactly what we are talking about. It's built-in source of drag, not a parachute/anchor.
I'd say their transmission was knackered or one of their rear calipers was already binding. Engine braking can't lock tyres (assuming tarmac, not ice).
Slamming down gears and pulling out the clutch to lose speed is not the same thing, at all.
I am talking about exactly the same situation as you. Just simy coming down a slope at a perfectly sensible pace and using engine braking as part of your means of maintaining a suitable speed and controlling it.
It is really very simple. Under engine braking conditions you are only braking with the driven wheels. There is a very good reason why brakes work on all wheels. RWD is obviously less forgiving than FWD. Again for really rather obvious reasons.
Stickyfinger said:
DonkeyApple said:
Yes and agree but was just highlighting that you are still only braking with the driven wheels and on rwd cars I've seen them spin off doing exactly what we are talking about.
then they are going to fast, have chosen the wrong gear and are nobs ....that's like saying brakes are bad because you lock them up by going to fast and stamping on them at the wrong time and to hard
Edited by Stickyfinger on Wednesday 29th July 17:02
Thank you for everyones reply.
Today I drove for four hours, I didn't use the clutch uphill or downhill, and it went very well.
For a very steep hill, I will always use second gear, and will use first gear if its a steep hill, as soon as I move off. For example if I am coming out of a car park and theres a very steep hill, like the one in st ives.
Today I drove for four hours, I didn't use the clutch uphill or downhill, and it went very well.
For a very steep hill, I will always use second gear, and will use first gear if its a steep hill, as soon as I move off. For example if I am coming out of a car park and theres a very steep hill, like the one in st ives.
Thank you for everyones reply.
Today I drove for four hours, I didn't use the clutch uphill or downhill, and it went very well.
For a very steep hill, I will always use second gear, and will use first gear if its a steep hill, as soon as I move off. For example if I am coming out of a car park and theres a very steep hill, like the one in st ives.
Today I drove for four hours, I didn't use the clutch uphill or downhill, and it went very well.
For a very steep hill, I will always use second gear, and will use first gear if its a steep hill, as soon as I move off. For example if I am coming out of a car park and theres a very steep hill, like the one in st ives.
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