Can match reving hurt your trans or clutch ? when down shifting?

 

Nope. Quite the contrary. You actually SHOULD do it. Even better would be double clutching (the bigger the downshift the more important this is) but it's not absolutely necessary.

 

You actually can "double declutch" to rev match i.e. lift off the throttle, press down your clutch and put it into neutral, lift off the clutch and match to the higher rpm of the lower gear (whatever that may be...needs to be memorized what rpm = what speed you are going in that particular gear), press down your clutch again and shift into the lower gear.

This is definetely not necessary as Terran said however it is a skill and all part of the manual experience. I rarely do the double clutch and rather blip my throttle while the clutch is depressed without going into neutral and then depressing the clutch again.

And no it will not do harm unless you seriously f*k up somewhere along the line.

 

yea its definatelly a good thing, saves wear and tear on your synchros.