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Discussion Starter · #1 ·
First I'll explain what it is I do, and then wait for the flood of OMGWTFs...

Just messing around, I discovered some odd combination of double-clutching and rev matching that may or may not have a name. If, for instance, I'm in 3rd at 3k RPM, shift to neutral, and release the clutch, what I do is spool up to 2k RPM, pop the clutch, slide it into 4th, and let off the clutch. Just as with double-clutching, the stick slides into 4th with no resistance, and when I let off the clutch I don't feel a thing, assuming I've hit the RPMs correctly.

So, is this bad (besides the obvious waste of gas)? Is it murder on some obscure bearing? Seems to me it is highly conservative on both the clutch and the synchros, since they have to do very little work, but since I've never heard of a person trying this before I kinda wondered why...
 

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You basically rev matched your upshift. I do what you do for my 1-2 shift. The resistance you feel otherwise during a shift are the synchros working. You could just double clutch it if you want instead, since you've felt that it's the same effect. Pulling this off during a race launch is tougher though. It's cool that you're trying things to be gentle on the car, unlike some of the SI's I see around here flooring it at red lights and dropping the clutch in their 1-2 shifts
 

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Increased wear on the master/slave cylinders in the clutch system, increased wear on the throw out bearing, and possibly the clutch assembly itself (springs, friction plate). I did it pretty regularly on the 6 and the clutch made it to 100k fine. The clutch did feel a little off. Bled it and not much help. I replaced the slave cyl right before I sold it. Old cyl actually seemed fine (no fluid in boot, etc). Think it was giving it a really good bleed and adjusting the pedal that did the trick. So no, 100k and the clutch survived.
 

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i don't think its gonna save a shit load of wear on the synchros assuming you just shift quickly to begin with. I mean in realistically you don't even have to put the clutch in at all in order to upshift.....its a lot easier for synchros to slow down naturally during an upshift just by shifting quickly that there is no really huge difference in speed between any of the moving parts...atleast not nearly as much as when you are downshifting and you need to bring some parts up to speed to deal with the sudden RPM increase
 

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Not saying you care, but anyone on the side of the road listening to you drive probably thinks you're an idiot. It sounds like an awful lot of work for daily driving lol, but you said you were just messin around.
 

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I reread your OP, and I wonder what exactly I was thinking when I replied. I most likely misinterpreted what you were doing.

So you...
1. clutch in
2. Hold in and let RPMs drop in 3rd
3. Rev to 2k
4. upshift to 4th.

I don't do that at all, lol. I just wait a bit in my 1-2 shift, but don't wait long enough that the RPMs fall to 1k.
 

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Almost every time I upshift I rev match. Or, I shift quick enough so that my RPM's don't get below what they will be at once the gear is fully engaged. I try to release the clutch at the proper RPM. This way, I'm only pressing the clutch in and releasing it once, but since I'm rev matching at the same time (by releasing the clutch at the right time), it's less wear all around.

When braking, I usually use my brakes rather than the syncros because brakes are a lot cheaper to replace.
 

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engine breaking ... if done right ... gives a lot of satisfaction ... If you are truly "tuned in" to your car ... you instinctively know when to slip the clutch and decrease speed.
 

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Discussion Starter · #9 ·
[quote author=filphil link=topic=139999.msg3019748#msg3019748 date=1238111563]
I reread your OP, and I wonder what exactly I was thinking when I replied. I most likely misinterpreted what you were doing.

So you...
1. clutch in
2. Hold in and let RPMs drop in 3rd
3. Rev to 2k
4. upshift to 4th.

I don't do that at all, lol. I just wait a bit in my 1-2 shift, but don't wait long enough that the RPMs fall to 1k.
[/quote]

Actually, no... What I do is the following (the difference being the clutch):

1. Clutch in
2. Shift to neutral
3. Clutch out
4. Rev match and hold at 2k
5. Clutch in
6. Shift up (still holding my revs at 2k)
7. Let off clutch

My understanding of double-clutching is that for it to work, you have to let off the clutch while in neutral (something to do with getting the drivetrain up to speed? Not sure I understand the whole process). Instead of "blipping" the throttle, I hold it, maybe fine-tuning it if I give it too much. Takes much longer to shift if I goof it up, and if I'm off I do feel a lurch when I let off the clutch after shifting, but more often than not I get it right.
 

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[quote author=COOL 3 link=topic=139999.msg3022321#msg3022321 date=1238204389]
engine breaking ... if done right ... gives a lot of satisfaction ... If you are truly "tuned in" to your car ... you instinctively know when to slip the clutch and decrease speed.
[/quote]

I find engine braking satisfying....engine breaking...not so much :lol:
 

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[quote author=budgy link=topic=139999.msg3038798#msg3038798 date=1238879648]
[quote author=COOL 3 link=topic=139999.msg3022321#msg3022321 date=1238204389]
engine breaking ... if done right ... gives a lot of satisfaction ... If you are truly "tuned in" to your car ... you instinctively know when to slip the clutch and decrease speed.
[/quote]

I find engine braking satisfying....engine breaking...not so much :lol:
[/quote]

LMAO
 

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[quote author=Ridicalis link=topic=139999.msg3038735#msg3038735 date=1238876899]
[quote author=filphil link=topic=139999.msg3019748#msg3019748 date=1238111563]
I reread your OP, and I wonder what exactly I was thinking when I replied. I most likely misinterpreted what you were doing.

So you...
1. clutch in
2. Hold in and let RPMs drop in 3rd
3. Rev to 2k
4. upshift to 4th.

I don't do that at all, lol. I just wait a bit in my 1-2 shift, but don't wait long enough that the RPMs fall to 1k.
[/quote]

Actually, no... What I do is the following (the difference being the clutch):

1. Clutch in
2. Shift to neutral
3. Clutch out
4. Rev match and hold at 2k
5. Clutch in
6. Shift up (still holding my revs at 2k)
7. Let off clutch

My understanding of double-clutching is that for it to work, you have to let off the clutch while in neutral (something to do with getting the drivetrain up to speed? Not sure I understand the whole process). Instead of "blipping" the throttle, I hold it, maybe fine-tuning it if I give it too much. Takes much longer to shift if I goof it up, and if I'm off I do feel a lurch when I let off the clutch after shifting, but more often than not I get it right.
[/quote]

probably feeling the lurch because of holding the gas instead of blipping it....really I don't see the purpose in doing all of this on an upshift.....downshifting 2+ gears I can see the point, except instead of holding the gas, just blip the throttle while putting it into gear and be off the gas by the time your clutch is out again
 

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why do you even double clutch on the upshift from 3 > 4? If you are in 3rd gear @ 3k rpm, just shift into 4th and let out the clutch when the rpm's hit 2k. I dont feel any resistance and should go into gear easily.

I dont see how double clutching will work on an upshift - when you double clutch you are revving in neutral to bring the rpm's to match the HIGHER rpms in a LOWER gear (ie 3rd to 2nd). No??
 

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[quote author=mazda3memelvin link=topic=139999.msg3048049#msg3048049 date=1239245512]
why do you even double clutch on the upshift from 3 > 4? If you are in 3rd gear @ 3k rpm, just shift into 4th and let out the clutch when the rpm's hit 2k. I dont feel any resistance and should go into gear easily.

I dont see how double clutching will work on an upshift - when you double clutch you are revving in neutral to bring the rpm's to match the HIGHER rpms in a LOWER gear (ie 3rd to 2nd). No??
[/quote]
+1 if you get your shift timing correctly, you would only need to clutch in, shift, then clutch out right as the RPM's fall into the next gear (for up shifting). took me a few weeks to get used to it when i first learned stick.
 
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