Rev Matching

[Phluvcat]

Hello

 

people have been talking about how rev matching brings you a smoother ride and minimise stress to the engine. Correct me if I got the terms wrong...two methods are widely use - double de-clutching and heel-and-toe.

 

So I curious once in a blue moon will try try a bit.

 

Till date, maybe due to my pedal arrangement, I find it difficult to do heel and toe. Or I do not have the flexibility of a ballerina. And every time when I am in the mood to try, after several attempts, in addition to not getting anything right, I appear to temporarily forget even my normal pedal movements, i.e. I felt like a newbie. And I will like take a few seconds before I feel like myself again.

 

Lately tried double de-clutching, way easier but find it too troublesome on Singapore roads, when I am making so many gear changes.

 

In the end, I just drive as per normal. As long as when I down shift at the appropriate speed and gradually release the clutch no noticeable jerk can liao.

 

So my question is - the above is also a form of rev matching right? Just that its prob not suitable for tracking. Anyway the engine is designed to take reasonable stress.

 

Another questions that pops up - every time blip throttle when executing the 1st two method, in theory will up the fc right?

 

Regards.

[1fast1]

Hello

 

people have been talking about how rev matching brings you a smoother ride and minimise stress to the engine. Correct me if I got the terms wrong...two methods are widely use - double de-clutching and heel-and-toe.

 

So I curious once in a blue moon will try try a bit.

 

Till date, maybe due to my pedal arrangement, I find it difficult to do heel and toe. Or I do not have the flexibility of a ballerina. And every time when I am in the mood to try, after several attempts, in addition to not getting anything right, I appear to temporarily forget even my normal pedal movements, i.e. I felt like a newbie. And I will like take a few seconds before I feel like myself again.

 

Lately tried double de-clutching, way easier but find it too troublesome on Singapore roads, when I am making so many gear changes.

 

In the end, I just drive as per normal. As long as when I down shift at the appropriate speed and gradually release the clutch no noticeable jerk can liao.

 

So my question is - the above is also a form of rev matching right? Just that its prob not suitable for tracking. Anyway the engine is designed to take reasonable stress.

 

Another questions that pops up - every time blip throttle when executing the 1st two method, in theory will up the fc right?

 

Regards.

 

To operate the clutch normally is to let the car (specifically, the synchromesh) do the rev-matching for you. So it's not considered "rev-matching" because you're not really doing anything active to match the lower gear engine speed to the road speed. You still cause synchromesh wear - which is within normal limits of wear and tear for street driving, but can destroy your gearbox after a long track session. Riding the clutch (like you describe) makes for smoother street-driving, but is not the answer to track driving, it'll just slow things down and cause excessive clutch wear as well.

 

This site : http://www.drivingfast.net/car-control/rev-matching.htm might help you.

 

Blipping the throttle does drive up FC a bit, but it's insignificant for streetdriving (as the transient increases in engine speed are insufficient to really make an impact). And on track, who gives a crap, right?

[Zomgpow]

You may find it hard because of the position of the pedals, some cars have pedals shaped specifically to aid in heel and toe, I only find it effective in preventing the wheels from locking, or under hard braking.

Edited January 1, 2011 by Zomgpow

[Sosaria]

...

 

In the end, I just drive as per normal. As long as when I down shift at the appropriate speed and gradually release the clutch no noticeable jerk can liao.

 

...

 

As my driving instructor used to say, to minimise jerk, "hands (shift gear) faster, foot (release clutch) slowly". Taking too long to shift gear, the rev drop below optimum, hence there is mismatch and jerking.

 

Best for rev matching... just get an auto car

 

[Good-Carbuyer]

Hello

 

people have been talking about how rev matching brings you a smoother ride and minimise stress to the engine. Correct me if I got the terms wrong...two methods are widely use - double de-clutching and heel-and-toe.

 

So I curious once in a blue moon will try try a bit.

 

Till date, maybe due to my pedal arrangement, I find it difficult to do heel and toe. Or I do not have the flexibility of a ballerina. And every time when I am in the mood to try, after several attempts, in addition to not getting anything right, I appear to temporarily forget even my normal pedal movements, i.e. I felt like a newbie. And I will like take a few seconds before I feel like myself again.

 

Lately tried double de-clutching, way easier but find it too troublesome on Singapore roads, when I am making so many gear changes.

 

In the end, I just drive as per normal. As long as when I down shift at the appropriate speed and gradually release the clutch no noticeable jerk can liao.

 

So my question is - the above is also a form of rev matching right? Just that its prob not suitable for tracking. Anyway the engine is designed to take reasonable stress.

 

Another questions that pops up - every time blip throttle when executing the 1st two method, in theory will up the fc right?

 

Regards.

There are many factors involved, so I shall simplfy as follows:-

I assume the road if flat, straight and free of obstructions

After starting the car, I would check if it is clear to drive off

If clear, Signal to drive off

Engage 1st gear, step a little on the accelerator, gradually release the clutch, apply more pressure onto the accelerator if needed

Step on the clutch pedal, engage 2nd gear, gradually release the clutch, and apply pressure onto the accelerato

Repeat for 3rd gears, 4th gears, 5th gears

Do not that my car got lower kerb weight, so this procedure dones no harm to the engine, and is smooth like automatic gear

 

[Kakabobo]

get a CVT gearbox.

sure smooth.

[Phluvcat]

To operate the clutch normally is to let the car (specifically, the synchromesh) do the rev-matching for you. So it's not considered "rev-matching" because you're not really doing anything active to match the lower gear engine speed to the road speed. You still cause synchromesh wear - which is within normal limits of wear and tear for street driving, but can destroy your gearbox after a long track session. Riding the clutch (like you describe) makes for smoother street-driving, but is not the answer to track driving, it'll just slow things down and cause excessive clutch wear as well.

 

This site : http://www.drivingfast.net/car-control/rev-matching.htm might help you.

 

Blipping the throttle does drive up FC a bit, but it's insignificant for streetdriving (as the transient increases in engine speed are insufficient to really make an impact). And on track, who gives a crap, right?

 

Thanks bro for the info. I am not a track person so if normal gear changing method is ok, then is ok for me.

 

I just wanna do or try it when I am driving leisurely. Tried double de-clutching a lot recently and it gives smooth transition during downshifting. As for h&t, my ankle gotta twist almost 90 degree, wah cannot..very dangerous wait I sprain my ankle during driving and become the joke of the town!

 

Anyway, street driving (in Singapore) not as predictable as tracking on a circuit. Too many factors where you have to brake, change gears, things like that. So I guess, most of the time this can leave it to the track then.

 

Thanks again and wishing you a Happy Rabbit Year!

[ER-3682]

Get the 370z manual,it came with Rev matching as standard.

[Phluvcat]

As my driving instructor used to say, to minimise jerk, "hands (shift gear) faster, foot (release clutch) slowly". Taking too long to shift gear, the rev drop below optimum, hence there is mismatch and jerking.

 

Best for rev matching... just get an auto car

 

You talking about upshifting?

 

yep but partially true. for the clutch release part, the roughly first 25 to 30% of the travel is fast and then slow considerably for the rest of the pedal travel and gradually releasing it. Different car different release pattern lah, need to establish the biting point and accustom your clutch control from there.

 

Its like fast, slow then gradual kind of movement, else whole process is slow the rev will drop too much. I keep my rev drop about between 500 and 1000 most of the time (if I recall correctly, the drop is less than one big tick, which represent 1000 rpm). Anyway I am talking about upshifting here.

 

I think so, been driving so long that I dun think about it and recalling what I precisely do in a car is a problem....

 

 

anyway, auto is good for town driving perhaps but not my cup of tea, its boring, can consider paddle shift next time but I do not think I can afford the COE and I dun feel its worthwhile anymore by the time comes.

 

More good years for you!

[Phluvcat]

There are many factors involved, so I shall simplfy as follows:-

I assume the road if flat, straight and free of obstructions

After starting the car, I would check if it is clear to drive off

If clear, Signal to drive off

Engage 1st gear, step a little on the accelerator, gradually release the clutch, apply more pressure onto the accelerator if needed

Step on the clutch pedal, engage 2nd gear, gradually release the clutch, and apply pressure onto the accelerato

Repeat for 3rd gears, 4th gears, 5th gears

Do not that my car got lower kerb weight, so this procedure dones no harm to the engine, and is smooth like automatic gear

 

 

???

 

Bro I very curious what is your age...

[Plim72]

Hello

 

people have been talking about how rev matching brings you a smoother ride and minimise stress to the engine. Correct me if I got the terms wrong...two methods are widely use - double de-clutching and heel-and-toe.

 

So I curious once in a blue moon will try try a bit.

 

Till date, maybe due to my pedal arrangement, I find it difficult to do heel and toe. Or I do not have the flexibility of a ballerina. And every time when I am in the mood to try, after several attempts, in addition to not getting anything right, I appear to temporarily forget even my normal pedal movements, i.e. I felt like a newbie. And I will like take a few seconds before I feel like myself again.

 

Lately tried double de-clutching, way easier but find it too troublesome on Singapore roads, when I am making so many gear changes.

 

In the end, I just drive as per normal. As long as when I down shift at the appropriate speed and gradually release the clutch no noticeable jerk can liao.

 

So my question is - the above is also a form of rev matching right? Just that its prob not suitable for tracking. Anyway the engine is designed to take reasonable stress.

 

Another questions that pops up - every time blip throttle when executing the 1st two method, in theory will up the fc right?

 

Regards.

 

 

to execute a clean heel toe easily, the rev must be reasonably high to begin with. try them on a track and you get what i mean. it will be way easier to do it than on public road where your speed would have to be reasonably fast at that high rpm.

 

[Requiemdk]

Short of finding a long deserted stretch of road where you can get up to reasonable speeds to practise your heel-toe technique, I find the best alternative is to practise it when exiting expressways at the slip roads where you can do a 5th to 3rd downshift. It'll come naturally after a while and you'll love it when your downshifts are actually smoother and more seamless than a conventional auto gearbox's. But beginners usually don't do the rev matching properly because they're unfamiliar with the rpms that they have to blip up to.

[Good-Carbuyer]

???

 

Bro I very curious what is your age...

So sorry for being long-winded. This technique no age restriction (laugh)

[Phluvcat]

So sorry for being long-winded. This technique no age restriction (laugh)

 

no lah, myself also deng kwee one...perhaps we about the same age...

 

[XALmoN]

Short of finding a long deserted stretch of road where you can get up to reasonable speeds to practise your heel-toe technique, I find the best alternative is to practise it when exiting expressways at the slip roads where you can do a 5th to 3rd downshift. It'll come naturally after a while and you'll love it when your downshifts are actually smoother and more seamless than a conventional auto gearbox's. But beginners usually don't do the rev matching properly because they're unfamiliar with the rpms that they have to blip up to.

 

i've noticed on my R, its a 500rpm difference between gears. but its been awhile since i've driven that car, all auto cars in singapore.

 

imo no point doing heel toe (mainly because i can't coordinate), so i just double clutch.

[Requiemdk]

i've noticed on my R, its a 500rpm difference between gears. but its been awhile since i've driven that car, all auto cars in singapore.

 

imo no point doing heel toe (mainly because i can't coordinate), so i just double clutch.

 

Same for my old manual Vios, where I learnt the technique on. Not much point to doing heel-toe instead of double clutching on the street really, but it's essential when driving balls out on the limits on the track. I used to do it on the street because it feels shiok

[1fast1]

] I used to do it on the street because it feels shiok

 

Same here. I perfected my technique in my bugeye WRX. Then when I sold it and bought a manual Kia Rio, I treated that as a beater. I used that car to practice clutchless shifting. Upshifts weren't an issue (just had to time it right), but downshifts had to be precise within +/- 200 revs max (even lower tolerance in the lower gears), otherwise, the gears would grind horribly. Got to the point where I could undertake entire journeys without the clutch, except when for the shift to first at lights.

 

Lots of advanced techniques can (and should) be honed on the street before driving on the track in anger. But one has to be careful - I remember the first time I tried left foot braking on the street. I simply did not expect to make an unintended e-brake, and I was lucky not to get rear-ended (in hindsight, I was foolish to have attempted that in traffic, but I underestimated the importance of muscle memory).

Edited January 1, 2011 by Turboflat4

[Bicolor]

Hello

 

people have been talking about how rev matching brings you a smoother ride and minimise stress to the engine. Correct me if I got the terms wrong...two methods are widely use - double de-clutching and heel-and-toe.

 

So I curious once in a blue moon will try try a bit.

 

Till date, maybe due to my pedal arrangement, I find it difficult to do heel and toe. Or I do not have the flexibility of a ballerina. And every time when I am in the mood to try, after several attempts, in addition to not getting anything right, I appear to temporarily forget even my normal pedal movements, i.e. I felt like a newbie. And I will like take a few seconds before I feel like myself again.

 

Lately tried double de-clutching, way easier but find it too troublesome on Singapore roads, when I am making so many gear changes.

 

In the end, I just drive as per normal. As long as when I down shift at the appropriate speed and gradually release the clutch no noticeable jerk can liao.

 

So my question is - the above is also a form of rev matching right? Just that its prob not suitable for tracking. Anyway the engine is designed to take reasonable stress.

 

Another questions that pops up - every time blip throttle when executing the 1st two method, in theory will up the fc right?

 

Regards.

 

The heel-and-toe technique feels extremely unnatural at first. I tried to master the technique for a long time but unlike double de-clutching, it was much harder due to the unnatural position of the right foot rotating to blip the throttle while braking at the same time. But this is all muscle memory, do it all the time (at first, only at a slow speed at gradual corners) and it becomes as natural as any other aspect of driving. The action has since become ingrained in me after nearly a year of practice that I can do it quickly enough not only to take corners but to brake to a stop quickly but smoothly when needed.

 

As others have mentioned, some cars have the brake and accelerator pedals too far from each other to perform this technique. In which case, for normal road driving, it isn't really necessary anyway.

 

The normal method of downshifting as you described is not a form of rev-matching. The synchromesh works to bring engine speeds up when you downshift, so no human effort is involved. Of course the vast majority of people drive this way and at normal road speeds it doesn't do much harm, although releasing the clutch too gradually may in theory cause more clutch wear.

 

Regarding your last question, not necessarily. A lot of factors are involved when it comes to FC. From my own experience in my first car, the first year I drove it without much attention to rev-matching while in the second year I double-clutch every single shift. My FC actually improved in the second year. Of course I can't say if this is due to the rev-matching, many other factors may have been involved, but it definitely did not cause any decrease in FC.

Edited January 1, 2011 by Bicolor