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Forgive me for my ignorance, but what is double clutching? I see it used in alot of racing topics, but have never seen a definition.
 

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Forgive me for my ignorance, but what is double clutching? I see it used in alot of racing topics, but have never seen a definition.
Double clutching is performed during downshifting (can be done during upshifting, as well, but not as common.....except in larger trucks with 10+ gears) to match revs between shifts. This is done in order to bring the flywheel/clutch to the RPMs needed for the next lower gear (in downshifting). The sequence is:

(while driving in some higher gear....eg: 5th)
- Clutch in
- Gear box in Neutral
- Clutch out
- throttle to appropriate RPM level
- Clutch in
- Gear box in next lower gear
- Clutch out

It takes a LOT of practice to be proficient at this. We had to do this in the Skip Barber 3-day racing school as the cars you use do not have synchros -- which is when you generally need to double clutch.
 

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so this method really isnt needed for the z?
no. And the Z's pedals aren't setup for it anyway. It's very hard to properly double clutch in the Z, although it's doable -- just REALLY tough compared to a car that does have a proper pedal setup.
 

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There's no reason to double-clutch in a car with synchros, so no it's not required in the Z. Actually, it won't help you during racing or daily driving either. It'll just make the job of driving a lot harder. :werd:
 

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no. And the Z's pedals aren't setup for it anyway. It's very hard to properly double clutch in the Z, although it's doable -- just REALLY tough compared to a car that does have a proper pedal setup.

I don't see what pedal location has to do with it. :dunno:

The Z doesn't need to be double clutched due to having synchros as you and Buddy stated.
 

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I don't see what pedal location has to do with it. :dunno:
Pedal position has nothing to do with "why" you double clutch, but it does have to do with how easy it is to perform. If you've ever driven a car that has pedals designed for racing, you know what I mean. For example, the Skip Barber Formula Dodge has adjustable pedals making it able to be tailored to each individual driver. Ideally, you want the brake pedal pretty close to the accelerator and when you depress the brake pedal, it should be as flush with the accelerator as possible. That way you can roll your foot over to the accelerator with minimal effort.

Here's a very rough sketch of what the pedals were like in the formula dodge....
[attachmentid=12308]

The Z doesn't need to be double clutched due to having synchros as you and Buddy stated.
Correct. That's three for no double clutching in the Z.
 

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My profession is Instructing on a race track. :) So, yes, I've seen a few race cars.

I understand what you are saying as far as pedal position for heel-toe. But I was more thinking about the actual double clutching action. Unless you are just stating that for easier foot work.

Oh well. :cheers:
 

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Double clutching is appropriate in certain situations. Any time you shift into first or reverse you should double clutch. A lot of people aren't aware of that and wonder why it's hard to get into gear or why the gears grind. I double clutch on a daily basis.
 

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If your "granny shifting and double clutchin" for pinks we have learned it a bad idea.
 

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Double clutching is appropriate in certain situations. Any time you shift into first or reverse you should double clutch. A lot of people aren't aware of that and wonder why it's hard to get into gear or why the gears grind. I double clutch on a daily basis.

When I put it in reverse, I simply shift to first gear, than go to reverse.. This is not really double clutching to me. You are just making the input shaft happy.

Double clutching is more so when you are moving in a forward gear and want to smooth engage into the next gear without the use of synchros.

Since Reverse doesn't have any synchros that I'm aware of.. that is why I shift into first gear prior to reverse.


Same idea... but different. I wouldn't call shifting into reverse in this fashion double clutching. The meaning of Double Clutching has been lost in translation somewhere.. People mis use it on a daily basis.
 

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while driving in some higher gear....eg: 5th)
- Clutch in
- Gear box in Neutral
- Clutch out
- throttle to appropriate RPM level
- Clutch in
- Gear box in next lower gear
- Clutch out

u completely lost me here. I thought it was lets say ur speeding in 3rd gear.. rpm gets to about 5 u press on the clutch release then switch into 4th.... am i wrong guys? This whole topic has got me confused with the synchros and such. please explain like people would on a 3rd grade reading level. :)
 

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u completely lost me here. I thought it was lets say ur speeding in 3rd gear.. rpm gets to about 5 u press on the clutch release then switch into 4th.... am i wrong guys? This whole topic has got me confused with the synchros and such. please explain like people would on a 3rd grade reading level. :)

Double clutching is just as he has explained:

while driving in some higher gear....eg: 5th)
- Clutch in
- Gear box in Neutral
- Clutch out
- throttle to appropriate RPM level
- Clutch in
- Gear box in next lower gear
- Clutch out


You don't have to double clutch a modern car with synchros. Just match RPM for the next gear and drive on. Don't forget to use 6th. Everything else has been explained in this topic.

If you need more help, go to howstuffworks.com
 

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When I put it in reverse, I simply shift to first gear, than go to reverse.. This is not really double clutching to me. You are just making the input shaft happy.

Double clutching is more so when you are moving in a forward gear and want to smooth engage into the next gear without the use of synchros.

Since Reverse doesn't have any synchros that I'm aware of.. that is why I shift into first gear prior to reverse.


Same idea... but different. I wouldn't call shifting into reverse in this fashion double clutching. The meaning of Double Clutching has been lost in translation somewhere.. People mis use it on a daily basis.
You should be aware that BOTH first and reverse do not have synchros therefor it is proper to double clutch those gears regardless. That doesn't mean you can't get into the gears without double clutching, it's just not as nice if you don't. Read your owners manual if in doubt. Selecting first gear before going to reverse does nothing beneficial and is a waste of time unless you're already in first.

For a real world daily driving scenario: Say you're backing out of a parking place. You push the clutch in and select reverse. Once backed out and stopped you push in the clutch and take it out of reverse and release the clutch while in neutral, then you depress the clutch again and select first. It is a double clutch any way you look at it and it is proper. Just going from first to reverse or vice versa in one swoop is not correct technique.
 

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Selecting first gear before going to reverse does nothing beneficial and is a waste of time if you're not already in first.

I have no problem putting the car into gear without double clutching. I suppose technically it is double clutching, but I don't think about double clutching when I'm going from REV, to 1st. or vice versa.

Then again. I don't slam the car in gear anyway. If it is difficult in the scenario you speak of, I do put it into neutral.. But I don't call this double clutching.. I call it putting it into neutral. :)
 

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Double clutching is a way to match the engine speed to the speed of the input shaft.

I am not moving when I shift into reverse.. So I don't consider this double clutching. As it's not difficult to match a input shaft that isn't spinning.

But you are correct, it's easier to put it into reverse this way. However, I believe the question at hand was "what is it" and "when do you need to do it". The answer, imo, is you don't need to do it.
 

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Double clutching is just as he has explained:

while driving in some higher gear....eg: 5th)
- Clutch in
- Gear box in Neutral
- Clutch out
- throttle to appropriate RPM level
- Clutch in
- Gear box in next lower gear
- Clutch out
You don't have to double clutch a modern car with synchros. Just match RPM for the next gear and drive on. Don't forget to use 6th. Everything else has been explained in this topic.

If you need more help, go to howstuffworks.com

I guess if i understood i wouldnt have asked the question... i guess its hard to some people to explain at 3rd grade level. thought u were a teacher? btw was this site developed to assist those who do not understand for those who only know the ins and outs of the 350z?
 

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I guess if i understood i wouldnt have asked the question... i guess its hard to some people to explain at 3rd grade level. thought u were a teacher?

I am. But I don't have to teach anything to people I don't want to teach. I was kind enough to reply and repeat the procedure in case you missed it. But, all you want to do is give a smart ass reply.

If you are having trouble understanding and need a pic, go to howstuffworks.com

Read the procedure again. It has been defined there and also by other members.



I'm not sure why you have a problem with what I posted. You want to be a smart ass, and I'll treat you like one. Double clutching has been defined and described in several ways throughout this topic. If you need more help, try google. Not sure why you have a problem with what I posted. It is clearly defined by the other members here as well.
 

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I am. But I don't have to teach anything to people I don't want to teach. I was kind enough to reply and repeat the procedure in case you missed it. But, all you want to do is give a smart ass reply.

If you are having trouble understanding and need a pic, go to howstuffworks.com

Read the procedure again. It has been defined there and also by other members.



I'm not sure why you have a problem with what I posted. You want to be a smart ass, and I'll treat you like one. Double clutching has been defined and described in several ways throughout this topic. If you need more help, try google. Not sure why you have a problem with what I posted. It is clearly defined by the other members here as well.
If you dont want to teach to someone you dont want to then why respond? U could have let others respond who are willing to help another member on this forum. If I wanted to get info from another site i would not be registered to this forum nor would i visit... i guess its too much to ask a question here anymore. Obviously if you read my response you would see that i copied and pasted what was explained and said quite clearly.... "YOU COMPLETELY LOST ME HERE" I am not sure if that was so hard to understand. The problem that i have with what u posted is if u asked me the definition of a word and i responded using that word in the definition would u understand the definition? I dont think so. Also josh asked the same question and did anyone refer him to another site? no not really so why do it to me? If you dont want me here chris then dont respond to my post. simple enough.
 
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