Synchronized downshift rev-matching system is a technology invented by Nissan for use on the Nissan 370Z.

Why do you rev match?

Why Do You Need To Rev Match? Changing down to a lower gear without properly adjusting your speed can cause excess strain on your engine, clutch and gears. By matching the revs, your car won't jerk forwards due to engine braking which you may have experienced whilst driving in the past.

How do you rev match?

Press on the gas pedal and “blip” the throttle, or bring the engine rpm up back up to increase the engine speed. Shift into the lower gear and then lift off the clutch pedal like normal. Ideally, the engine speed should match the lower gear that you're shifting into, hence the term “rev-matching”