Edmund's: Nissan 370Z's SynchroRev Match Heals Ham-Hands, Two Left Feet

[JeepZen]

Another article on rev matching. Not really any new information, but it describes the physical mechanics a bit better than most articles do and provides some insightful observations and opinions. The "it's seems so simple, why has no one else done it already?" question is one I have asked myself.

Nissan 370Z's SynchroRev Match Heals Ham-Hands, Two Left Feet

Hey, hotshoe. Think you're good at matching revs when you're downshifting? The 2009 Nissan 370Z's SynchroRev Match can do it better.

And if you're one of those drivers that has wondered why all this "heel-toe" business requires your two feet to do three things simultaneously, then you, too, can benefit from SynchroRev Match.

SynchroRev Match is a feature that automatically "blips" the throttle when the driver initiates a downshift in manual transmission-equipped 370s. If you depress the clutch, lift off the throttle and move the gearchange lever to a lower gear, SynchroRev Match zips the engine up to precisely the right speed for that gear.

The result? Perfectly smooth rev-matched downshifts every single time, and drivers that look like heroes.

Rev-matching is common among automatic- and automated-manual transmissions, but the 2009 Z-car marks the debut of such a feature in conjunction with a real-life, stick-in-the-palm manual gearbox.

Now, come with us to the other side of the jump to learn how it works.

SynchroRev Match is all zeros and ones--there is no black box or additional hardware. The 370Z's engine controller simply compares the engine speed to the data being fed by the rear wheel speed sensors. Since it "sees" the gear lever position and "knows" all of the gear ratios in the transmission, simple math dictates what the engine speed needs to be when you go for, say third gear at 60 mph.

Once the clutch is depressed and the lever slotted into the 3rd gear gate, the engine controller jumps into action. It snaps the throttle open exactly the right amount to achieve that target engine speed. By the time the clutch is re-engaged, the shafts at both ends of the transmission are already spinning at the same speed.

On the track, this allows you to better focus on your braking points while still impressing that hottie in the paddock with your snappy downshifts. Engine braking in slow-and-go street driving is much easier, too, thanks to the way that the system allows seamless engagement of first gear.

No adjustment by the driver is necessary, either. You can continue to go through the motions of manually blipping the throttle during downshifts if it makes you feel better. SynchroRev Match operates transparently so that you just drive the way you normally would.

Of course, there will always be the traditionalists that lambast electronic features such as this one for interfering with the driving experience. That's why Nissan fitted an "off" switch that remains in the setting you choose, even if you turn the car off. Take that, Luddites.

According to Nissan insiders, the company created SynchroRev Match "because they could," and is an idea they've been refining for a few years. That the system undoubtedly reduces wear and tear on the transmission's synchros must create a nice warranty upside, too.

The brilliance of the system is its simplicity and that it can benefit drivers of all stripes. Basically, any car with an electronic throttle, anti-lock brakes and gear position sensors in the transmission could conceivably offer this feature. That list doesn't preclude many cars these days.

It's one of those ideas that is so obvious that nobody else thought to introduce it.

Jason Kavanagh, Engineering Editor

[JeepZen]

Some of the comments are interesting as well.

You can skip as many gears as you like and it always blips to the correct engine speed. It won't try to over-rev the engine, of course.

The gear position sensors detect the gear you choose as the lever enters each gate. From there, the system just calculates the rpm needed and makes it happen.