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rev matching?

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Old 01-21-2009, 04:34 PM
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is rev matching better than just letting the clutch out softley when down shifting? and what is the correct way of rev matching? pls respond with any opinions. thx
Old 01-21-2009, 04:44 PM
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Yeah, It's easier on your clutch and provides a smoother transition between gears. What you want to do is match your engine speed(RPM) and your transmission speed before letting out the clutch.

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Old 01-21-2009, 04:46 PM
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Originally Posted by 00TAM6
is rev matching better than just letting the clutch out softley when down shifting? and what is the correct way of rev matching? pls respond with any opinions. thx
Yes, it is better to rev match than the just let the clutch out.

By rev matching, you are eliminating the wear and tear on the clutch that results from it having to match 2 different speeds, being that of the input shaft on the trans and the speed of the engine.

The proper (racing derived) way to downshift is to "heel and toe", which involves using your left foot on the clutch (as always), and using the heel of your right foot to press the brake and slow down as you use the tip of your right foot to blip the gas pedal to the proper RPM for the next gear you are selecting.

When I'm just cruising around though I'll blip the throttle on downshifts to rev match without touching the brakes, and just use the engine to slow me down until I'm near my stopping point, at which point I'll apply the brakes and disengage the clutch.

It takes a while to get a feel for the amount of throttle you have to give it between gears and at different RPM's, but once you start practicing you can usually just blip it and be within a couple hundred RPM of your target for the next gear.
Old 01-21-2009, 04:50 PM
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thanks for the input..
Old 01-21-2009, 04:59 PM
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Another thing I do is when I blip the throttle, I try to let out the clutch as the revs are falling down. Basically, I'd blip it a little higher than the desired RPM and then let the clutch out as it gets near the RPM I want. It allows for smoother downshifts IMO
Old 01-21-2009, 05:37 PM
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wow yall manual guys really do play with your sticks a lot.
Old 01-23-2009, 12:23 AM
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Yes rev matching is better than just letting the clutch out softly. You don't need to consider the clutch, it is the syncro's in the transmission that need the help from wear and tear. When downshifting for maximum accelaration bring the revs into the power band and let er rip. With stock 3.42 gears if I'm cruising below 37 I select 1st gear below 67 I select 2nd gear above that 3rd. I don't recall ever needing to down shift into fourth (I swear Mom). I'm sure some on here have though.
Old 01-23-2009, 11:59 AM
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yeah i think i got my rev matchin down..
Old 01-23-2009, 12:10 PM
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after reading this i am totally confused. what is rev matching?
Old 01-23-2009, 12:19 PM
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rev matching is a way of down shifting that is less wear n tear on your clutch n tranny..
Old 01-24-2009, 09:31 AM
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Rev matching is with the clutch in bringing the RPMs of the engine to match the RPMs the engine will be at with the clutch out in the selected gear:
So from a 55 mph cruise in 5th gear rpm ~1400 downshift to 2nd gear and while the clutch is in bring the engine no load rpms up to ~3700 and let the clutch out while mashing the loud pedal.
Old 01-24-2009, 12:56 PM
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Originally Posted by KENS_SS_4
Yes rev matching is better than just letting the clutch out softly. You don't need to consider the clutch, it is the syncro's in the transmission that need the help from wear and tear. When downshifting for maximum accelaration bring the revs into the power band and let er rip. With stock 3.42 gears if I'm cruising below 37 I select 1st gear below 67 I select 2nd gear above that 3rd. I don't recall ever needing to down shift into fourth (I swear Mom). I'm sure some on here have though.
Not trying to call you out, but rev matching doesn't benefit the synchros in the transmission at all. Just the clutch itself.

Double clutching is the only technique that benefits the synchros, which involves releasing the clutch, pulling the shifter into neutral, selecting the proper RPM with the throttle, putting the clutch in again, and then engaging the next gear.
Old 02-03-2009, 07:23 PM
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Originally Posted by Wesmanw02
Not trying to call you out, but rev matching doesn't benefit the synchros in the transmission at all. Just the clutch itself.

Double clutching is the only technique that benefits the synchros, which involves releasing the clutch, pulling the shifter into neutral, selecting the proper RPM with the throttle, putting the clutch in again, and then engaging the next gear.
I double clutch on a daily basis, its especially nice when going through a turn and you want to power through. Double clutching does not transfer weight like normal downshifting does. When you double clutch right you doing even feel it engage the lower gear which keeps the car smooth.
Double clutch coming up to a turn, slightly tap the brakes and at the apex let her rip, assuming you have enough room and can control your car and not hit a curb
That last part wasnt coming from personal experience, i swear.



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