Comment by left-struck
4 days ago
Oh man yeah the advice about continuous motion is not right. A clutch is a torque control device, in the case of a car it’s more like a torque limiting device. The more you let the pedal out the more torque you allow the engine to apply to the wheels up until the point where the torque you allow exceeds the engine’s available torque at a given rpm and throttle position. So if you’re constantly letting the clutch out you’re ramping up the torque limit linearly but the engine speed and wheel speed don’t match and if the engine speed is low of course the engine can easily stall.
Instead what you want to do, what most people do subconsciously is let the clutch out partially until it is allowing the engine to apply some of its available torque but not all, and then pause there until the car’s speed roughly matches the engine speed, at which point the clutch will stop slipping even though you still have the pedal partially depressed, after which you should be able to rapidly raise your foot from the clutch and feel no acceleration or deceleration. For an experienced driver that pause is less than like half a second from standstill. Also technically the point at which you want to pause the clutch let out depends on a whole bunch of things like how quickly you want to pull off, how much torque the engine can provide and whether you’re on a hill etc, but we just do this intuitively with experience.
This is like a super over-complicated way to think about it and I would never try to teach a learner driver by first explaining this lol but the point is, you find the engagement point and hold there for a while and then release when the car is moving. This is what we all do but it helps to understand why we do it so we don’t explain things wrong.
I feel like people also don’t get what applying more throttle does while the clutch is slipping. All it does is raise the engine rpm, it will apply absolutely no more torque (and therefore acceleration) no matter how much you press down the throttle. While the clutch is slipping the clutch pedal controls your torque and therefore acceleration. You need some throttle though to give you some room for error and some minimum torque to work with.
The funny thing is when I first started learning to drive, it seemed impossible to get right without stalling or bunny-hopping or something else going wrong. Yet now after years of driving it feels like there's a huge window of acceptable throttle and clutch. Apply tons or throttle or hardly any. Release the clutch carefully or quickly. Car always starts great. There must be so much muscle memory magic to it. I don't think I could bunny-hop the car anymore if I tried.
Let's not forget modern cars have "throttle adaptations" and will automatically compensate for the driver's lack of throttle input. If you just release the clutch pedal slowly, the engine will rev itself enough not to stall and the car will start moving.
I've also noticed you can release all pedals while driving these days and instead of eventually slowing to a stall, the car will only slow until it's happily rolling along in gear at some sort of very slow minimum speed. I presume that's the same feature?
1 reply →
Release the clutches linearly in half a second with the engine at 1k rpm and bunny hop away lol
But you’re totally right. You can pull away quickly by letting your rpm build up and choosing an aggressive clutch position while applying enough throttle to keep the rpm constant, alternatively in most cars you can pull away on a fairly steep hill with no throttle if you just barely let the clutch engage and hold it at that point until the car is moving steadily