[nicktechla]

Originally Posted by Lethal Z

The DMV in the US does not require you speak or read english or are even a legal citizen to issue a license in many states....do you really think they give a crap about the proper downshifting procedure...

you don't have to be a legal citizen, you could be a green card holder.

[DenverTaco07]

Give me active rev match or


give



me




death

[Cupahaters]

Okay so is it better to use rev match and down shift when driving then to push in clutch and just slow down?

[JamesNoBrakes]

Originally Posted by Cupahaters

Okay so is it better to use rev match and down shift when driving then to push in clutch and just slow down?

Question: Why does that slow you down? The answer is friction. Think about it.

[EDFHOBBIES]

Rev match I use it all the time in wifes SS and the my Zl1.. It takes longer to actually engine break or slow the car down..Seems to coast more, It helps my wife all the time me 1 or 2 times a year If I'm accelerating 3rd to 4th and by chance go to 2nd it saves the motor from breaking a spring possibly or spinning a bearing! I hear it go off and move the gear shift vs letting the clutch out. It's a great aid at the track for instructors to teach inexperienced drivers, instructors can hear if the driver is changing gears when or not needed and using engine braking vs over braking w the brakes..

[Norm Peterson]

Originally Posted by ctrlz

At any rate, you can continue to slow the car by downshifting and enjoy the sounds. I personally would never do this on a regular basis because: 1) downshifting only uses 2 wheels to slow the car, whereas brakes use 4 wheels; and, 2) downshifting like this will save the brakes at the expense of prematurely wearing the clutch. This is the fundamental reason not to downshift: brakes are much cheaper to replace than a clutch.

Downshifting as a replacement for using the service brakes to come to a stop is not a normal reason for downshifting (though you might want to use the technique should the car's brakes actually fail).

One reason you would downshift is to put the transmission in a gear better suited to an upcoming need for acceleration that doesn't involve coming to a full stop first. IOW, predicting what gear you'll be wanting ahead of time instead of reacting to acceleration that's unsatisfactory (or all the way into 'lugging').

Another reason would be for speed control on the kind of long downgrades you don't see very often in the southern and coastal areas of NJ - if for no other reason than the fact that continuously lit brake lights won't tell the driver behind you that you suddenly stepped on the brakes even harder.

If downshifting alone is the reason for anybody prematurely wearing out the clutch, they're doing it wrong.


Norm

[Norm Peterson]

Originally Posted by Lazerbrainz2k3

A well executed rev match when downshifting will produce a negligible additional amount of wear on the clutch as compared to engine braking without shifting. The catch is you have to be very skilled to execute the rev match that well all the time when done manually, a level of skill the auto rev match feature emulates.

All it takes is practice. Practice to get there, and practice after that to stay in practice. It really isn't all that tricky of a technique to pick up.


Norm

[Norm Peterson]

Originally Posted by Cupahaters

Okay so is it better to use rev match and down shift when driving then to push in clutch and just slow down?

Sometimes (and for this specific question I don't care if it's you or the electronics doing the rev match). It really depends on the situation of the moment.


Norm

[torqueaddict]

Originally Posted by Norm Peterson

Downshifting as a replacement for using the service brakes to come to a stop is not a normal reason for downshifting (though you might want to use the technique should the car's brakes actually fail).

One reason you would downshift is to put the transmission in a gear better suited to an upcoming need for acceleration that doesn't involve coming to a full stop first. IOW, predicting what gear you'll be wanting ahead of time instead of reacting to acceleration that's unsatisfactory (or all the way into 'lugging').

Another reason would be for speed control on the kind of long downgrades you don't see very often in the southern and coastal areas of NJ - if for no other reason than the fact that continuously lit brake lights won't tell the driver behind you that you suddenly stepped on the brakes even harder.

If downshifting alone is the reason for anybody prematurely wearing out the clutch, they're doing it wrong.


Norm

Well said. Predicting the need for speed and the prevention of unnecessary lugging are two big reasons.

[Lazerbrainz2k3]

Originally Posted by Norm Peterson

All it takes is practice. Practice to get there, and practice after that to stay in practice. It really isn't all that tricky of a technique to pick up.


Norm

Generally speaking, yes. But again, the computer still does it better than you will, and as relating to the topic at hand, with less wear than doing without the automatic function.

[torqueaddict]

Originally Posted by Lazerbrainz2k3

Generally speaking, yes. But again, the computer still does it better than you will, and as relating to the topic at hand, with less wear than doing without the automatic function.

Sure, the computer will always calculate the correct RPMS based on input. Still, as I pile on the miles and get more used to this car's driving dynamics, I find myself doing it manually more and more. It's just more fun. And I don't know if it's just me, but I get better engine braking with Active Rev Matching off.

Yes it smooths everything out, both up and down (yes it does it on the upshifts too from what I read and tested myself - could be mistaken though). And yes, downshifts are buttery smooth, addictingly so, but actual engine braking, while it's there and can be felt, is less than when ARM is off. Does anyone else notice this?

[JamesNoBrakes]

Originally Posted by ctrlz

At any rate, you can continue to slow the car by downshifting and enjoy the sounds. I personally would never do this on a regular basis because: 1) downshifting only uses 2 wheels to slow the car, whereas brakes use 4 wheels; and, 2) downshifting like this will save the brakes at the expense of prematurely wearing the clutch. This is the fundamental reason not to downshift: brakes are much cheaper to replace than a clutch.

If using rev-match (or doing it manually), doesn't this put the wear on the engine? More specifically something like the rings, as with rev-match it's like not using the clutch at all, it'll be engaged, but not slipping, which is where most of the wear comes from?

[Norm Peterson]

Originally Posted by Lazerbrainz2k3

Generally speaking, yes. But again, the computer still does it better than you will, and as relating to the topic at hand, with less wear than doing without the automatic function.

I think once the revs are matched within some tolerance there isn't going to be much difference between human rev-matching and the computerized version. Though the computer would be less likely to get 'sloppy' and miss the target rpm.

Done manually with decent timing, there isn't going to be much power being transferred across the clutch until it is fully re-engaged. Way, way less than what's needed for a normal start from a full stop using 1st gear or reverse.


Norm

[Norm Peterson]

Originally Posted by JamesNoBrakes

If using rev-match (or doing it manually), doesn't this put the wear on the engine? More specifically something like the rings,

Very doubtful it'd amount to anything you'd be able to measure - all it is as far as engine wear is concerned is a few extra crankshaft revolutions at only the low power needed to accelerate the moving parts up to the rev match target rpm. Peanuts compared to accelerating the whole car even mildly.


Norm