Honda first introduced the DOHC VTEC mechanism in the US on the 1990 Acura NSX. But a year earlier in 1989, the Japan Domestic Market got the world’s first dose of DOHC VTEC in the 1989-1993 generation of the Honda Integra. The 1989 DA6 Honda Integra RSi/XSi used a 160ps variant of the B16A DOHC VTEC engine. Honda enthusiasts would recongnize the B16A engine since it is currently used in the 1999 and 2000 US-spec Civic Si and Canada-spec Civic SiR. However the B16A used in the current Civics is a second version of the original B16A. The main difference is that the newer US-spec B16A has slightly more power at 160hp.

Graph 1 Okay that’s enough history. Lets see how DOHC VTEC works. The figure to the right shows a simplified representation of a intake-valve VTEC mechanism (the exhaust mechanisms work similarly). So for each pair of valves, there are three cam lobes. The two on the outside are low RPM lobes and the one in the middle is the high RPM lobe. The two low RPM lobes actuate the two valve rockers, which in turn pushes the valves open. The high RPM lobe actuates a follower, which is shaped like a valve rocker, but doesn’t actuate any valves. The figures show the circular section of the cam lobes touching the valve rockers, and the eliptical section pointing away. Thus the valves are closed in this stage.

Graph 2 During low RPM operations, the two outer cam lobes directly actuates the two valve rockers. These low PRM lobes are optimized for smooth operation and low fuel consumption. The high RPM lobe actuates the follower. But since the follower isn’t connected to anything, it doesn’t cause anything to happen. This procss is illustrated by the figure to the right.

Graph 3 At high RPMs, oil pressure pushes a metal pin through the valve rockers and the follower, effectively binding the three pieces into one. And since the high RPM lobe pushes out further than the low RPM lobes, the two valve rockers now follow the the profile of the high RPM lobe. The high RPM lobe’s profile is designed to open the valves open wider, and for a longer duration of time, thus allowing more fuel/air mixture to enter the cylinder. The improved breathing allows the engine to sustain its torque output as RPM rises, thus resulting in higher power output

DOHC VTEC That is basically how VTEC works. The picture to the right is a picture of an actual DOHC VTEC engine. Note that there are two cam shafts, one for the intake valves and one for the exhaust valves. For each pair of valves, notice that there are three cam lobes: two cam lobes on the outside, and one cam lobe in the middle.

As I’ve said before. The VTEC mechanism is nothing spectacular. DOHC VTEC is the most ambitious of all VTEC varieties in terms of specific output (except for the up coming VTEC-i). Yet as you can see, the implementation is elegantly simple. VTEC is Honda’s solution to the design goal of improving engine breathing at high RPMs while retaining smooth and economical operation at low RPMs. DOHC VTEC technology is currently used in the 160HP Civic Si, 170HP Integra GS-R, 195HP Integra Type-R, 200HP Prelude base/Type-SH, 240HP S2000 and the venerable 290HP Acura NSX. And these are just the US-spec cars. Saying that VTEC is a successful design is an understatement.

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For three decades, Honda has played a leading role in meeting environmental challenges.

The Civic Hybrid is living proof that environmentalism and style can go hand in hand.
Power at the PumpThe benefits of the refined gasoline-electric powertrain on the Civic Hybrid are never more evident than when you watch those little numbers adding up at the pump. And with an EPA-estimated city/highway rating of 40 city/45 hwy mpg,* you’ll spend a lot less time there at the gas station.Help Clear the AirThe air also benefits with the Advanced Technology Partial-Zero-Emission Vehicle (AT-PZEV)† rating, which is the most stringent

Be good to yourself while being good to the earth.Far from AustereDriving a vehicle that reduces your impact on the planet can still be good fun.
The Civic Hybrid with available Honda Satellite-Linked Navigation System™ with voice recognition* now offers Bluetooth® HandsFreeLink®†. And a CD/CDR/CDRW/MP3 audio system with Honda’s new USB Audio Interface** makes it easier to rock out while you ride. Complete the look with a new 3-spoke steering wheel.Leather Adds LuxuryA new Leather trim is available for 2009, and it will satisfy your senses with a leather-wrapped steering wheel, heated front seats and heated side mirrors.Fuel-Friendly ReminderAnd just to remind you it is a hybrid you’re driving, Honda has included a handy Average Fuel Consumption Indicator.

The ingeniously fuel-efficient* Civic Hybrid is the picture of performance.
Efficiency Rules
The Honda hybrid technology Integrated Motor Assist IMA® system consists of a super-efficient 1.3-liter, 8-valve i-VTEC ® 4-cylinder gasoline engine paired with a lightweight, high-output electric motor, which adds extra power when needed.Feels Almost EffortlessThe Civic Hybrid is outfitted with a smooth continuously variable transmission (CVT), which combines the ease of an automatic with the efficiency of a manual. An idle-stop feature automatically shuts off the Hybrid’s gasoline engine when you stop, so you help keep the air cleaner.

The Civic Hybrid helps protect you and your precious passengers with leading-edge safety technology.Safety EssentialsEssential safety features such as side curtain airbags and dual-stage, dual-threshold front airbags (SRS) are standard on the Civic Hybrid. Vehicle Stability Assist™ (VSA®) was added in 2009 for increased protection.Keep it safe out there.The Advanced Compatibility Engineering™ (ACE™) body structure spreads out the crash energy in impacts with vehicles of differing sizes. All four doors feature side-impact beams designed to help prevent intrusion into the passenger space. Other important safety features such as 3-point seat belts with front seat automatic tensioning system for all seats, and an anti-lock braking system (ABS) add peace of mind.

Rather than a rigid-beam suspension, Honda chose an independent strut-type suspension that allowed the left and rear wheels to move independently.

The new Honda Civic is here – and yet again it’s set to break the mould in the family hatchback sector! These exclusive shots show how the next car will look when it hits the showroom in 2010, and as you can see, the Japanese maker has opted for a shape that is even bolder and more individual than the current model.

With Vauxhall set to launch a stylish new Astra, and the next, sleek Ford Focus due in 2010, competition is fierce – but Honda has pulled out the stops to create a real stunner. As revealed in Issue 1,023, the OSM concept seen at the British Motor Show was more than simply an ‘Open Study Model’ – as the face of the new Civic is almost identical.

There are hints of VW’s IROC concept, which was toned down to become the Scirocco, in the gaping front grille. The new hatchback adds elements carried over from the current Civic, too, most notably the trademark single strip light cluster at the rear. But Honda fans will note that the split rear screen has been dropped to improve visibility. Shallow glass areas, broad shoulders and a nose-down stance give this three-door model a sporty and purposeful look.

The hatchback ‘coupé’ pictured here will be aimed at younger buyers, who want style and image more than outright practicality. So, as well as big alloys and a contrasting black bodykit, the three-door gets lowered suspension and a dark interior with deeply sculpted seats.

The three-door will be distinct from the five, as Honda adopts an approach similar to the Renault Mégane by pitching the two cars at different buyers. So, the five-door will be more for the family, with a taller roofline offering plenty of space, a bigger boot, plus a softer ride and handling balance.

The engine line-up will be shared between the two styles, though, and our sources have revealed that a 1.5-litre IMA hybrid engine with more than 150bhp and sub-CO2 120g/km emissions will appear.

In fact, the Civic will herald a change in focus for the Japanese maker as it seeks to reduce CO2 emissions. It’s currently restructuring manufacturing facilities to cater for large-scale hybrid production.

Over the next five years, Honda plans to power all four-cylinder cars using either petrol hybrids with lithium-ion batteries or i-CTDi diesels. But it is also introducing ‘deactivation technology’ for its V6, V8 and V10 engines. This means that some
cylinders will not be used in more relaxed driving conditions in an attempt to improve efficiency.

Hot hatch fans will also be well catered for, as a Type R flagship is in the works, powered by a 2.0-litre i-VTEC engine which, given Honda’s five-year hybrid plan, could be boosted by an electric motor. This would make it the world’s first hybrid hot hatch!