Explaining matching revs on downshifts?

[Ari]

My girlfriend asked me at the weekend why I blip the throttle when I shift down a gear. I know why I do it, but trying to explain about matching the revs to the next gear down, and why (reduced wear on the clutch etc), I found really hard.

Is there any good videos or explanations on the Internet that anyone knows of?

[maniac0796]

Say it makes the ride smoother.

Or tell her the perfect gearchange is "unnoticable except for a change in engine note."

[davepoth]

It saves wear on the clutch, gearbox and engine mounts. But most importantly of all it sounds cool.

[5lab]

it should save tyre wear (minutely) as well, as the engine isn't slowing the car through the tyres

[LukeBird]

Tried explaining this to a friend of mine when I gave her a lift.
I gave up.

It would be easier to teach Norwegian to a monkey.

[Baryonyx]

It contributes to the smoothness and stability of the drive by matching the road speed to engine speed etc etc.

[Ari]

Yes yes, but why?

I understand perfectly about bringing the engine revs up to road speed in the lower gear thus no clutch drag etc, but explaining how that works to someone is not easy.

[Evo]

Also if you driving quickly ie trackdays then matching engine revs to your gear change can help the cars stability on entry to a corner, a little bit of heel and toe never goes amiss though i do find it almost as hard to convince the other half as explaining how aeroplanes manage to stay in the air (which i have to do every year we go on holiday )

[Ari]

5lab said:

it should save tyre wear (minutely) as well, as the engine isn't slowing the car through the tyres

Depends why you're slowing surely? If you're braking for a corner then blipping to an appropriate lower gear then the tyre wear of reducing speed will simply be caused by the brakes instead.

[Ari]

maniac0796 said:

Say it makes the ride smoother.

Or tell her the perfect gearchange is "unnoticable except for a change in engine note."

Ah, but she changes down without blipping and is totally smooth, as lets the clutch in gently she says. (And to be fair she's right, she's a very smooth driver. It's just that matching the engine revs is more "correct" and reduces wear).

[vonhosen]

Ari said:

My girlfriend asked me at the weekend why I blip the throttle when I shift down a gear. I know why I do it, but trying to explain about matching the revs to the next gear down, and why (reduced wear on the clutch etc), I found really hard.

Is there any good videos or explanations on the Internet that anyone knows of?

Tell her to imagine she is running on a treadmill in the gym blindfolded, she gets lifted off & the placed back on it. Would she want it moving at the same speed she is running at when she is put back on, or at a wildly different speed ?

[Ari]

davepoth said:

It saves wear on the clutch, gearbox and engine mounts. But most importantly of all it sounds cool.

Ahh, but she's never had to replace a clutch in a car she's owned, ever.

(You're right about the sounding cool of course, but that's entirely subjective ).

[Ari]

vonhosen said:

Tell her to imagine she is running on a treadmill in the gym blindfolded, she gets lifted off & the placed back on it. Would she want it moving at the same speed she is running at when she is put back on, or at a wildly different speed ?

See, I used the landing aeroplane wheel analogy. Imagine bringing the landing gear wheels up to landing speed, no smoke or screeching of tyres on touchdown as speed would match.

"What's that got to do with changing gear?"

You see my problem?

[Ari]

Evo said:

though i do find it almost as hard to convince the other half as explaining how aeroplanes manage to stay in the air (which i have to do every year we go on holiday )

Ah, the old low pressure over the wing creates lift thing?

See, I reckon the wing pushes air down and that lifts the plane, so you'd probably have the exact same problem with me there.

[vonhosen]

Ari said:

vonhosen said:

Tell her to imagine she is running on a treadmill in the gym blindfolded, she gets lifted off & the placed back on it. Would she want it moving at the same speed she is running at when she is put back on, or at a wildly different speed ?

See, I used the landing aeroplane wheel analogy. Imagine bringing the landing gear wheels up to landing speed, no smoke or screeching of tyres on touchdown as speed would match.

"What's that got to do with changing gear?"

You see my problem?

Well if when you lift her off the treadmill, the speed of the treadmill is changed because it's in a different gear before you put her back on, if she isn't matching that speed when she is put back on she'll end up on her arse.

[Ari]

"So what's that got to do with changing gear? I don't blip the throttle, it's perfectly smooth, I've never needed a new clutch and I don't end up on my arse"

D'ya see?

I need moving diagrams and whatnot.

[vonhosen]

Ari said:

"So what's that got to do with changing gear? I don't blip the throttle, it's perfectly smooth, I've never needed a new clutch and I don't end up on my arse"

D'ya see?

I need moving diagrams and whatnot.

You don't need to have a rev on the down change if you drive in a manner that doesn't require it, but not everybody wants to drive like that though.

[Ari]

I agree, and she doesn't.

I'm not trying to get her to, I'm trying to explain why I do.

[Mr.Jimbo]

basically, you're doing what she's doing, making the gear change smooth, a lot quicker and with the throttle, not just slipping the clutch in.

[Dracoro]

Ari said:

"So what's that got to do with changing gear? I don't blip the throttle, it's perfectly smooth, I've never needed a new clutch and I don't end up on my arse"

Does she understand the treadmill analogy? Explain to her that every time she does it, it increases stress on her knees/ankles. If she is still understanding you, explain to her that if she did this many times, her knees/ankles would be shot in no time at all, she would be in a wheel chair in no time. If she tries to match her running speed when returning to the treadmill each time, she'll still be walking until she's old.