Rev Match Every Down Shift?

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Depends on the speed at which I downshift, but I do typically rev-match somewhat. Slipping the clutch to rev the engine up just puts a poopload of unnecessary wear on it, blipping the throttle just as you push in on the clutch works great and you can downshift pretty aggressively with very little clutch wear.

I do tend to downshift quite a bit- engine braking causes almost zero wear and Brembo brake pads aint cheap. :-/ But if you wear the clutch like crazy doing it, that's even more expensive!
 
I usually blip the throttle, but I don't watch the guage, looking to see if I have it within a few rpm's. Mostly I drive by feel: if I let the clutch out and feel a lurch, then next time I blip the throttle more on the same sort of shift. [My commute is pretty well set in stone, so I already know the spots where I plan to shift, and already know the spots where I will coast in 5th, shift to 3rd, coast then brake--or anything similar.]

I don't think I've ever tried double clutching.
 
I rev match on each and every downshift regardless if it's regular eco city driving or spirited cruising.

EXAMPLE: driving in 6th gear and slowing down for a turn. Hit the clutch @ around 1,200rpm and keep slowing down while going into 2nd gear. Blip the throttle to say 2,000rpm for 2nd gear @ 17mph and engage the clutch for a SILKY SMOOTH transition and off I go!

My wife used to just ease the clutch to bring up the engine revs but that surely put more wear and tear on the clutch / flywheel and why would you want to do that, if you can blip the throttle and match the engine & transmission speeds MANUALLY. This is also much quicker then easing the clutch.

Downshifting into a higher gear where the engine speeds are much faster is even more important for not only long clutch life but a smoother downshift in general. I can rev match / downshift from 6th gear into 3rd or even 2nd gear while doing 45mph faster then your average automatic transmission can do the same switch and my downshift is just as smooth as the auto.

Double clutching hasn't been NEEDED for PROPER downshifts for decades. Let the synchronizers do their job while you move the stick from a high gear to a lower one. If you're still double clutching while driving a modern manual transmission, you're wasting your time and energy and are also putting more wear and tear on the clutch throwout bearing and clutch master cylinder UNNECESSARILY!
 
My 2014 Mazda 3 w/ 2.0L shows 999mpg on the current mpg readout any time I'm in gear and let off the gas... how is this relevant to this thread though?
 
I rev match because it's fun, I occasionally double clutch as well... because fun.

I always rev match when I'm trying to hustle my car, because its a faster and smoother way of getting the engine's torque to the ground..... which is kind of important if you're braking and entering.

I'm a little confused as to why people are saying they don't rev match because of syncros. You don't rev match to reduce the burden on your syncros, you double clutch and rev match for that. The syncros aren't used to get the engine's speed to what it needs to be for whatever gear you're shifting to.
 
Originally Posted By: Artem
My 2014 Mazda 3 w/ 2.0L shows 999mpg on the current mpg readout any time I'm in gear and let off the gas... how is this relevant to this thread though?


Originally Posted By: Mykl
I rev match because it's fun, I occasionally double clutch as well... because fun.

I always rev match when I'm trying to hustle my car, because its a faster and smoother way of getting the engine's torque to the ground..... which is kind of important if you're braking and entering.

I'm a little confused as to why people are saying they don't rev match because of syncros. You don't rev match to reduce the burden on your syncros, you double clutch and rev match for that. The syncros aren't used to get the engine's speed to what it needs to be for whatever gear you're shifting to.


High MGP readings while letting off the gas is the engine's freewheel programming to save gas...

There's a tendency of many modern engines to continue to rev between gears on downshifts, just as they INCREASE RPMs a bit on their own between UPshifts to make shifting smoother...theoretically this will reduce wear on the throwout bearing as well as the syncros...and if making RPM matching less a necessity (for those who don't know how or don't bother) it remains perhaps a preferred behavior...
 
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I'll rev match on big aggressive downshifts, ie 5,4th to 2nd or sometimes a nice 2nd to 1st if I feel like being a riceboy and braking with 95% engine braking. Basically only when big RPM differentials are expected.
 
Originally Posted By: Mykl
I'm a little confused as to why people are saying they don't rev match because of syncros. You don't rev match to reduce the burden on your syncros, you double clutch and rev match for that. The syncros aren't used to get the engine's speed to what it needs to be for whatever gear you're shifting to.

Sometimes you feel like using the clutch. Sometimes you don't. Of course, neither rev-matching nor using the clutch...
 
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Knowing it can be done is good for situations when clutch release has failed. Broken clutch cable on a bug. Brought it home by rev matching up and down and feathering the engine by shutting it off and on. I just keep the trick stuff for emergencies. I had 30 yrs of driving commuters with automatic trans. Both the 528s are 4 speed automatics. Held in 2 or 3 and manually up shifting with the pedal floored. Simulating a power shift on a manual. The little I-6 loves it. The car will do 70 in 2. That is 5k RPM. I discovered this doing an Italian tuneup at about 330 k miles. Never bothered the transmissions.
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Originally Posted By: d00df00d
Every. Single. Downshift. Double-clutched and blipped (if not also rev-matched). No exceptions.


Double clutching does literally nothing for a synchronized transmission.
 
Originally Posted By: badtlc
Originally Posted By: d00df00d
Every. Single. Downshift. Double-clutched and blipped (if not also rev-matched). No exceptions.


Double clutching does literally nothing for a synchronized transmission.


It sure does because the synchronizers don't have to do any work, so it saves the synchros.
You can feel it while shifting as if the gear is "sucked in".

But in reality, if one is gentle and slow to shift during the warm up time, the synchronizers will see minimal wear, therefore double clutching will not make a difference in the grand scheme of things.
 
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Originally Posted By: badtlc
Originally Posted By: d00df00d
Every. Single. Downshift. Double-clutched and blipped (if not also rev-matched). No exceptions.


Double clutching does literally nothing for a synchronized transmission.


Try downshifting from 2nd to 1st on a rolling start in a VTEC B18C with and without double-clutch rev matching! You'll see
 
Count me as another in the "rev match but don't double clutch" crowd. I generally only downshift when needed to accelerate, when needed to maintain speed on a grade, or when entering a 35 zone from a 55, for example (i.e. not just on the way down from speed).
 
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