Who rev matches their downshifts?

Status
Not open for further replies.
So are all of you rev matching and not shifting with a clutch? Am i understanding you guys correctly? I don't understand why you would do that.
 
Easy PJ...
When you down shift the RPMs increase, just as when you up shift RPMs decrease...

Rev-matching is the process of increasing RPMs between shifts in N so when the lower gear is engaged there is no change in RPMs, and thus, friction between the clutch pressure plates is minimized...

Double-clutching is when you down shift 2 or more gears and you release the clutch (take your foot off the clutch) when the shifter is in N, and rev the engine to get the RPMs (much) higher to where it will be in the (much) lower gear.....

Double clutching is hardly necessary when downshifting 1 gear, e.g. 4th to 3rd....just revving the engine (a bit) between shifts is more than adequate to "rev-match" that downshift.
 
Last edited:
Originally Posted By: KitaCam
Easy PJ...
When you down shift the RPMs increase, just as when you up shift RPMs decrease...

Rev-matching is the process of increasing RPMs between shifts in N so when the lower gear is engaged there is no change in RPMs, and thus, friction between the clutch pressure plates is minimized...

Double-clutching is when you down shift 2 or more gears and you release the clutch (take your foot off the clutch) when the shifter is in N, and rev the engine to get the RPMs (much) higher to where it will be in the (much) lower gear.....

Double clutching is hardly necessary when downshifting 1 gear, e.g. 4th to 3rd....just revving the engine (a bit) between shifts is more than adequate to "rev-match" that downshift.


Thanks for the explanation. I do rev match when I'm paying attention, esp. when driving alone. If I'm having a conversation or changing the radio station, I tend to forget to do it.
 
I usually just burp the motor while it is clutched, so as to match the engine speed to what will be required, that way when I let out the clutch there is no jerk. That is the real reason to rev-match, less wear on the clutch, smoother driving.

I've tried double clutching a time or two ,but it feels really unnatural. Small quibble: double clutching doesn't care how many gears you move, it's to get the parts inside the transmission to the proper speed so that gear clash won't occur. When the syncro's wear the trans gears (or dogs) don't slide into each other very well; or if it's a non-syncronized transmission they just don't mess well at all, not unless if you slow down (or speed up?) the mainshaft.

I do double downshift/upshift very frequently in my cars, double clutching is not required for that.
 
Originally Posted By: MinamiKotaro
That's what the synchros are for.


Yes, true. But rev matching reduces/eliminates the "lurch" forward when downshifting. It especially helps when your passenger is prone to car-sickness anyhow.
 
Status
Not open for further replies.
Back
Top Bottom