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Discussion Starter · #1 ·
Topic states...
ALso what is hte proper technique for rev matching?
1) Press in clutch, shift into lower gear, tap the accelerator, release clutch or...
2) press in clutch, shift into neutral, release clutch, tap accelerator, push in clutch, shift into lower gear, release clutch..

I have heard both being tossed around.
 

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Re: What are good books on racing technique? Question about revmatching too... (HatchedGTI)

I usually press in the clutch, rev it, downshift, then release the clutch
 

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Re: What are good books on racing technique? Question about revmatching too... (HatchedGTI)

Quote, originally posted by HatchedGTI »

1) Press in clutch, shift into lower gear, tap the accelerator, release clutch or...
2) press in clutch, shift into neutral, release clutch, tap accelerator, push in clutch, shift into lower gear, release clutch..

#2. If you do #1, then you aren't accelerating the transmission gears to the same speed.
 

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Re: What are good books on racing technique? Question about revmatching too... (HatchedGTI)

best driving book i ever read:
http://www.amazon.com/exec/obi...07846
Vic is the master!
obin http://****************.com/smile/emthup.gif
 

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Re: What are good books on racing technique? Question about revmatching too... (vduBen)

Quote, originally posted by vduBen »
#2. If you do #1, then you aren't accelerating the transmission gears to the same speed.

Good to know next time you're driving a big rig or a car with a non-synchronized gearbox.
Worrying about the transmission input shaft speed is unnecessary if your synchros work. The simple rev-match without double-clutch will suffice to let the car decelerate smoothly, without slipping the clutch.
The only downshift I have ever double-clutched is 2->1.
 

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Re: What are good books on racing technique? Question about revmatching too... (AKADriver)

Quote, originally posted by AKADriver »
Good to know next time you're driving a big rig or a car with a non-synchronized gearbox.
Worrying about the transmission input shaft speed is unnecessary if your synchros work. The simple rev-match without double-clutch will suffice to let the car decelerate smoothly, without slipping the clutch.
The only downshift I have ever double-clutched is 2->1.

I think HatchedGTI is referring to racing. When braking at the end of the straight or into a corner you really need to get the disk/trans spinning up to the speed of the intended gear at which you plan to down shift, otherwise the rear end will break loose.
On the street, as far as clutch wear, it's a double sided coin. If you rev match, but don't double clutch, you'll wear on the disk when down shifting. If you double clutch routinely you'll wear on the PP springs and throwout bearing.
 

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Re: What are good books on racing technique? Question about revmatching too... (vduBen)

Quote, originally posted by vduBen »
I think HatchedGTI is refering to racing. When braking at the end of the straight or into a corner you really need to get the disk/trans spinning up to the speed of the intended gear at which you plan to down shift, otherwise the rear end will break loose.

The synchros do that for you when you select the gear while the clutch is in. The act of moving the shift lever from one gear to the next does all the work of speeding up or slowing down the transmission input shaft. No user input to the transmission input shaft speed is needed in a synchronized gearbox. The rev-match matches the engine speed to the transmission input shaft and clutch disc which are now spinning faster as they should for the next gear.
This effect was audible in my 240SX, which had some sort of noisy bearing in the front of the transmission. You could hear the speed of the transmission input shaft as a hum. If I pulled the lever back to second from third, you could hear the input shaft accelerate as the pitch of the hum increased.
Of course, on the race track in the 240SX, it was also proven as I never, ever, ever double-clutched it in a high-speed track situation.
 
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