aznguy370z

iTrader: (2)

This was posted on gdriver by riversideinfiniti. I find it interesting nissan claims a half second gear change. Most likely the 370z gets the same 7 speed as the infiniti.

Originally Posted by Nissan North America
Explaining the benefits of Infiniti’s new transmission

The target: create an automatic transmission with all the best features of a manual transmission. Here’s how Infiniti engineering gives drivers the best of both worlds.


The automatic transmission traditionally represented a compromise. It gave drivers the convenience of smooth, clutchless shifting, but it sacrificed the direct connection, driver control, and enhanced fuel economy of a stick shift.

Infiniti’s new 7-speed automatic transmission, available on 2009 FX35, FX45, G37 Sedan, G37 Coupe, and the upcoming 2009 M35 (rear-wheel-drive), takes the automatic closer than ever before to the feel and operation of a manual transmission.

No More “Slush-Box”

Slippage between the engine and transmission earned early automatics the nickname “slush-boxes.” The hydraulic clutch system for making gear changes could not operate as quickly or directly as a manual transmission’s mechanical clutch.

All modern automatics have a lockup torque converter, which limits slippage by creating a solid mechanical connection between the engine and transmission. For smoother operation over a wider range of operating conditions, newer designs vary the amount of converter lockup (from a 100% solid connection to a partial lockup condition).

Infiniti’s 5- and 7-speed transmissions use a multiple disc torque converter lockup design that allows the unit to “ease” into lockup, minimizing the shudder that can occur in single-disc designs.

While Infiniti is not the first manufacturer to vary the level of torque converter lockup, it has created an extremely wide available lock-up range with the new 7-speed transmission:

With the transmission in Drive, partial lockup is available in 2nd through 7th gears while full lockup occurs in 7th.
With the transmission in manual shift mode, both partial and full lockup are available in 2nd through 7th gears.
Some amount of lockup occurs at all throttle positions and at speeds greater than about 15 mph. The result? Infiniti's 7-speed transmission provides a more direct, solid-feeling connection than drivers typically expect from an automatic transmission.

In manual shift mode, a flick of the 7-speed’s shift lever makes the half-second gear change a reality.

Driver Control

For driving enthusiasts, one of the lures of a manual transmission is the control it gives them to select and maintain the gear they want. Several features of Infiniti’s new automatic transmission directly address this concern.

One of the foremost is manual shift mode. Consider this: for anyone other than a seasoned race driver, it generally takes more than half a second to make a smooth shift with a manual transmission — depress clutch, move shift lever, release clutch, apply throttle.

But in manual shift mode, a flick of the 7-speed’s shift lever (or available steering-column-mounted paddle shifters) makes that half-second gear change a reality.

For smoother downshifting, Downshift Rev Matching (DRM) mimics the heel-and-toe maneuver used by skilled drivers during manual transmission downshifts.

The 7-speed design targets both performance and fuel efficiency.


The 7-speed includes other features first seen on Infiniti 5-speeds, including:

Adaptive Shift Control, which enhances gear selection by using a lateral acceleration sensor to detect changes in the road (such as hills and turns).
Drive Sport Mode (DSM), which allows the driver to select a more aggressive shift pattern (automatic up- and downshifting at higher rpm).
Combined, these features allow any driver to enjoy quick, smooth shifts and gear choices that are appropriate to both the road and their desired driving style — some of the enthusiast’s main reasons for choosing a manual.

Enhancing Economy

Automatic transmission vehicles typically suffer a small penalty in fuel economy estimates when compared to their manual transmission counterparts. Infiniti’s 7-speed design targets not only performance, but also enhanced fuel economy:

The wide range of torque converter lockup operation maximizes engine efficiency (less power is wasted as slippage).
In previous 5-speeds, only 5th gear provided an overdrive ratio. Now both 6th and 7th gears are overdrive ratios, allowing the engine to operate at lower rpm during a broader range of highway speeds.
Owners may not understand the penalties they have paid in the past for the convenience of an automatic transmission. But whether drivers want “hands on” or “hands off” control, Infiniti’s new transmission will provide a satisfying driving experience.

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vnarang

iTrader: (7)

Interesting. I wouldn't be surprised if Nissan incorporated this.

Spoon_sports808

i wan't lexus's 8 speed auto's shift time =[

LeMans 05

iTrader: (1)

1/2 second seems a bit slow... Hopefully the Z will have a 'sport' mode that shortens those shifts.

Then again, what do I care, if I get a 370Z, it'll be a manual anyway

saturn

It seems with the advent of the DSG style transmissions most people are going to become even more opposed to the idea of torque converter style autos regardless of what fancy tech is inside them. This all seems like a stopgap solution until they can bring a DSG style transmission to the Z from the GT-R in a cost effective way.

Manjot

iTrader: (2)

Paddle shifters would totally rock

lonewolf

iTrader: (10)

1/2 a second? that's not something i'd choose to advertise

bauertt

In my opinion, I think we'll find the 370z with a 6 speed manual or 7 speed auto (not 5 speed like the G37C) and yes, paddle shifters will be present.

I always thought, standard for sure but after driving the new maxima with paddle shift and the new G37 with paddle shift, I'll grab an auto for the crappy times in traffic knowing when the road opens up, so does the shifting options. Sitting in traffic with a standard blows.

GodSendsDeath

iTrader: (1)

Honestly how many of you can shifter faster than that? I dunno maybe but if I get auto and that....hmmm or have to deal with the terrible manual that was in my 08 Z.

Spork

iTrader: (6)

I can generally shift in a second or less if I wanted

Manjot

iTrader: (2)

Made my day

350Zforlife

iTrader: (4)

Very impressive.. Hope the new Z gets this.

BaTMan_4

iTrader: (12)

automatic = boring...

black06z

iTrader: (1)

Very interesting, indeed. I still wish they developed a DSG for the upcoming models. After all, it is the future of trannys.

aznguy370z

iTrader: (2)

Got this from edmunds about the is-f. So .5 sec isn't so slow.

upshift times drop from a Lexus IS 350's typical 1.3 seconds (0.7 second to initiate plus 0.6 second to change ratios) to a mere 0.3 second (0.2 second to initiate plus 0.1 second to shift).

THe Emperor

iTrader: (4)

0.5 isn't all that slow. A friend on mine works for Nissan and got a chance to drive a GT-R. He said the computer has two modes for the shifting, one for regular driving which shifts at 0.5 and one for the track which shifts at 0.2. I read somewhere online that the average NASCAR driver shifts in 0.4.

mthreat

iTrader: (16)

I think modern Formula One gearboxes can shift in 0.015 seconds or so (15 milliseconds).

350z2k3

iTrader: (5)

What was wrong with your 08?

GodSendsDeath

iTrader: (1)

I hated my clutch. That thing used to sit so high up and if you wanted to shift you needed to press the clutch nearly through the floor board or you will hear a grind. I dunno maybe this is normal, all I used to drive prior this Z was BMW's and there manual's are a joy to drive.

Greg06

I for one hope the 370 doesnt get this type of trans... IMO Manual and or DSG trannys only for sports cars.

Leave the 7-8-9 or whatever speed (Their all just old *** torque converters) autos to the luxury types.