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VVEL Technology Briefing Variable Valve Event & Lift System July 13, 2007

Junichi Yajima Chief Powertrain Engineer Powertrain Engineering Division Nissan Motor Co., Ltd.

Agenda

1. The Powertrain Concept 2. Benefits of VVEL 3. VVEL Structure 4. VQ37VHR 1. The Powertrain Concept

1-1. Core Values of Nissan Technology Trusted Driving Pleasure Trust: ὉEnvironment Environment ὉSafety Driving Pleasure: ὉDynamic Performance DynamicDynamic ὉLife on Board PPerformanceerformance Safety Environment

Q uality , Cost 1-2. Powertrain Engineering Concept

ṲNissan's powertrain development aims to develop an ultimate powertrain which balances 3 factors [Emotion, Efficiency, Emission] at a high level Emotion Performance

Ultimate Powertrain Efficiency Emission CO2 reduction

1-3. VVEL Concept

ṲVVEL highly-balances 3 factors [Emotion, Efficiency, Emission]

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VVEL

EEfffificciieennccyy EEmmiisssiioonn 2. Benefits of VVEL

¾What is VVEL? ¾Benefits of VVEL

2-1-1. What is VVEL?

ṲConventional engines have one-type lobes, limiting it to one pattern of movement ṲVVEL combined with C-VTC enables continuous valve movement

Conventional Engine VVEL-equipped Engine

VVEL 2-1-2. What is VVEL?

ṲVVEL controls amount through intake-valves of the , where conventional engines used valves

Conventional Engine VVEL-equipped Engine

Throttle Throttle open open/close Variable intake Constant intake valve lift valve lift

The fixed cam which moves the Direct intake-air control with valve, enables intake-air control at continuously variable valve lift throttle valve opening

2. Benefits of VVEL

¾What is VVEL? ¾Benefits of VVEL 2-2-1. Benefits of VVEL – Fuel Efficiency (When throttle opening is small) ṲIn driving condition on a flat road at constantly 40km/h (when accelerator is pressed halfway or less) there is little pumping loss with VVEL-equipped engines

Conventional Engine VVEL-equipped Engine Throttle Valve Close Throttle Valve Open Negative Atmosphere Pressure Pressure Choking

Valve Throttle Big negative work (=non throttle) (pumping loss) little negative work

Similar condition to the large amount Similar to good condition where little of strength needed to pull a thin strength is needed to pull thick syringe syringe needle. (large pumping loss) needle. (little pumping loss)

2-2-2. Benefits of VVEL – Fuel Efficiency (When throttle opening is small) ṲIn driving ranges of small throttle opening, intake-valve lift can be kept low to reduce friction compared to conventional engine Cam shaft Friction

VVEL-equipped Engine Conventional Engine (small lift amount) (fixed valve lift) 2-2-3. Benefits of VVEL – Better Response

ṲVVEL-equipped engines control air amount at intake-valve by the combustion chamber entrance, which enables necessary air to be sent promptly to combustion chamber, resulting in better response.

Conventional Engine VVEL-equipped Engine

As air is controlled at the throttle valve far from the combustion Air instantly enters when chamber, it takes time to deliver accelerator is pressed necessary air

2-2-4. Benefits of VVEL – Better Response

ṲWith a short hose, water flows out right after the tap is turned (with VVEL)

without VVEL

with VVEL 2-2-5. Benefits of VVEL – Better Response ṲWith a long hose, when the tap is turned it takes a while before water flows out (without VVEL)

without VVEL

with VVEL

2-2-6. Benefits of VVEL – More Power Ṳ Torque is improved by optimized valve open-close movement, adjusted accordingly to engine revolutions

VVEL Engine

Conventional Engine

VVEL Engine Torque

Engine Speed 2-2-7. Benefits of VVEL – Cleaner Emissions 䂓 At timing of ignition when air is being warmed and combustion is unstable, if valve lift amount is small, air flow velocity rises. Fuel is then atomized by vaporizing effect and combustion is stabilized, resulting in clean emissions.

Valve Lift 2mm Valve Lift 8mm Average Particle Diameter 9㱘m Average Particle Diameter 157㱘m

2-2-8. Benefits of VVEL - Summary VVEL ṲVVEL is a system which controls the amount of air intake directly at the intake-valve right before the combustion chamber ṲVVEL combined with C-VTC, creates continuous movement of valve

Fuel ṲVVEL throttle valve remains open, causing little Efficiency pumping loss (little resistance) (when throttle opening is small) 䂓As valve lift amount is small, there is little friction

Better ṲAllows necessary air to be sent promptly to the Response combustion chamber, resulting in better response

More ṲTorque is improved by optimized valve open-

Benefits close movement, adjusted accordingly to engine Power revolutions

ṲAs VVEL stabilizes combustion even when engine Cleaner is cool, rise in exhaust emissions temperature Emissions enables quicker warm-up of catalyst, resulting in clean emissions 3. VVEL Structure

3-1. Basic Structure of VVEL System Nut Ball Screw Shaft

DC Motor

Rocker Arm Control Cam Control Cam (eccentric cam) (eccentric cam) Link B Control Shaft Link B Control Shaft Link A Output Cam Input Cam (oscillating cam) (eccentric cam) Drive Shaft Link A Drive Shaft Input Cam Output Cam (eccentric cam) Valve Lifter (oscillating cam) Valve Lifter FragmentaryFragmentary ViewView Valves (direction(direction ofof arrow)arrow) 3-2. Valve Lift Amount/Operating Angle Conversion Nut Ball Screw Shaft

DC Motor

Control Shaft Control Shaft

Output Cam (oscillating cam)

Output Cam (oscillating cam) FragmentaryFragmentary ViewView (direction(direction ofof arrow)arrow)

3-3. Valve Drive of VVEL System

Drive Shaft

Drive Shaft Valve Lifter Valve Lifter FragmentaryFragmentary ViewView Valves (direction(direction ofof arrow)arrow) 3-4. VVEL Motion

Maximum Lift Amount

Valve Operating Angle

Maximum Valve Lift

3-4. VVEL Motion

Maximum Lift Amount Lift Amount Lift Amount

Minimum

Valve Operating Angle Valve Operating Angle Valve Operating Angle

Maximum Valve Lift Minimum Valve Lift 3-4. VVEL Motion Lift Amount

Minimum

Valve Operating Angle

Minimum Valve Lift

3-4. VVEL Motion

ṲVVEL is capable of continuously changing valve lift amount (between min - max) freely

Minimum Valve Lift Maximum Valve Lift 4. New-Generation VQ37VHR Engine

4-1ώEvaluation of the VQ Engine

䂓 VQ35HR awarded “Ward’s 10 Best Engines” for 13 consecutive years

‘95‘96‘97‘98‘99‘00‘01‘02‘03‘04‘05‘06‘07 Nissan VQ

BMW I6

Ford V8

DCX V8

GM V6

Honda V6

Toyota V6 4-2. Aim of the New Generation VQ37VHR Engine 䂓 Based on the VQ35HR engine, further improvements on engine performance, fuel efficiency, and clean emissions Smooth, 1ὸ High rate of revolution pleasant Max 7500rpm drive ResponseResponse 2ὸ Pleasant acceleration sound ClearԈൢὉ sound੎ൢὉ༓໲јྙỉӼɥ ExhilarationExhilaration AccelerationAcceleration 3ὸ Top level power performance in class SoundSound ImprovedImprovedԈ intake/exhaust/combustionintake/exhaust/combustionൢὉ੎ൢὉ༓໲јྙỉӼɥ efficiencyefficiency

Fuel 4ὸ Increased practical fuel efficiency Efficiency ReducedԈൢὉ੎ൢ frictionὉ༓໲јྙỉӼɥ

Cleaner 55ὸὸ Best-in-classBest-in-class emissionemission standardstandard Emissions ṿṿԈṿṿൢṿṿὉ੎ṿṿൢὉ༓໲јྙỉӼɥ

4-3. Technology of VQ37VHR Engine New design for VQ37VHR Increased height of blocks Symmetric twin intake system Asymmetric skirt

Revised Sound insulating engine cover Equal length

Straight inlet port Enhanced durability of rocker High ignitability for iridium plug cover Enhanced durability of chain cover Lengthened High flow exhaust port Ultra-wide phase angle C-VTC on Hydrogen-free DLC valve lifters Extended amount of valve lift intake side Enhanced valve spring

VVEL system on air intake side Enlarged diameter of journal Revised oil pump rotor VQ37VQ37VHRVHR Revised diameter of valve Enhanced durability of upper oil pan Approx. 35% of parts Processing PVD Enhanced durability of lower oil pan newly developed Ladder frame set Enlarged diameter of crankpin M12 Cooling water flow structure Enhanced Twin knock sensor Extended cylinder block liner High flow intake manifold Thin-lined umbrella of intake valve Ladder frame of cam bracket High flow resin collector VVEL will be debut on the SKYLINE Coupe VQ37VHR engine to be launched this fall

Thank you for your attention