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A brief history, technical background, and rundown of notably awesome Honda cars that seek to answer the question, “What is VTEC?”
The Legend of VTEC
In the annals of automotive history, VTEC is a term uttered with reverence by enthusiasts and engineers alike. A landmark version of variable valve timing (VVT) invented by Honda, VTEC arrived over 30 years ago and has been on a redlining tear ever since. But, just in case you’ve ever wondered, “What is VTEC?”, we’re here to help with the history of this system, how it works, and some of the coolest cars to ever employ the high-revving wonders of VTEC.
But before answering that question, we need to answer another one, namely “What does VTEC stand for?” Technically, Honda calls it Variable Valve Timing and Lift Electronic Control, which is a mouthful. So instead, the automaker shortens it to Valve Timing Electronic Control (VTEC). Though this may sound like any other VVT system in the auto industry that changes valve timing, VTEC goes further by also modifying the camshaft profile and valve lift.
How Does VTEC Work?
Unlike conventional engine design that uses a single camshaft lobe and rocker arm per cylinder, VTEC uses a multi-part rocker arm and three camshaft lobes. Two of those lobes make up the low-RPM profile, which allows for a smooth idle, ample low-end torque, and solid fuel efficiency. The third larger lobe and its dedicated rocker arm segment, which is located in between the outer two, make up the high-RPM profile and aren’t engaged unless certain conditions are met.
Those conditions include specific values for engine oil pressure, engine temperature, vehicle speed, engine speed, and throttle position. Using those inputs, the ECU is programmed to switch from the low-RPM camshaft profile to the high-RPM profile as needed. At this switchover point, a pin is pushed from one of the outer rocker arms – using oil pressure – into the middle rocker arm, which in turn pushes a pin out of the middle rocker arm into the other outer arm.
At this point, all three rocker arms are locked together and operating as a single large rocker arm. But now, the larger central VTEC camshaft lobe is controlling the valves as it is the tallest of the three lobes. As a result, the valves open up higher and stay open longer which means more air and fuel can get in and out of the cylinder. Translation: more power. It also translates to a signature sensation when behind the wheel of a Honda that uses VTEC.
When you’re not expecting it, the sound can be startling as in “Did I just blow up the engine?” That terrifying thought is partly due to the fact that the high-RPM profile kicks in at, well, higher RPMs. So, if you’re standing on the gas in third gear and suddenly the engine gets VERY loud and everything goes faster, it can be alarming to see the tachometer spin towards 8,000 RPM and beyond. But then, you realize what’s happening and before you know it, VTEC addiction has set in.
Honda’s VTEC History
Why would Honda spend so much time and money on engineering such a complex mechanical system that at a glance, may seem only to juice the adrenaline of enthusiasts? For one thing, Japan has historically levied a tax on cars based on engine displacement. So, Japanese automakers have tended to focus on perfecting the performance of small engines. The “no replacement for displacement” mantra that American automakers famously lived by was not realistic in Japan.
Over time, as auto engineers chased performance, there have been notable efforts to keep displacement down, while delivering epic cars. Forced induction is an obvious approach that has led to loads of amazing vehicles like the turbocharged Toyota Supra and Nissan 300ZX and the supercharged Toyota MR2. Mazda famously went hard into rotary engines with its RX-7, and later RX-8, series. But Honda took a different route that led to VTEC.
It was in the 1980s when Honda launched its New Concept Engine program to push the limits of top-end torque while maintaining fuel efficiency and low-end performance. Ikuo Kajitani, an engineer on that team, is credited with zeroing in on the performance targets the team needed to achieve. Those targets were 100 horsepower per liter – relatively incredible at the time – with specific figures of 160 horsepower and an 8,000-rpm redline.
To hit these targets, the team went wild with a new high-strength sintered alloy that allowed for thinner camshaft gears, intake valves enlarged to 33 mm, camshafts made from a new high-carbon high-chrome cast steel alloy, and exhaust valves constructed from nickel-based steel blended with molybdenum, titanium, and tungsten.
Notable VTEC Vehicles
The final product was introduced as HYPER VTEC on a 1983 CBR400 motorcycle, but by 1989, the Honda Integra XSi became the first car to see VTEC usage. However, it was the 1991 Acura NSX that saw Honda’s VTEC technology land on American shores for the first time.
Like most early VTEC-powered cars, the NSX used a dual overhead cam (DOHC) engine. Though VTEC can be used with a single overhead cam (SOHC) engine, it wasn’t as beneficial in the early days because the VTEC mechanism only benefitted the intake valves due to the common – single – camshaft for intake and exhaust valves.
The NSX was, and is, an amazing car, but not the kind of car attainable by the masses. So, it was really the 1992 Acura Integra GS-R that turned American car enthusiasts onto the wonders of Honda VTEC. This was right around the time that the sport compact tuner market exploded in popularity and Honda could not have timed the arrival of its VTEC system any better.
In 1994, Honda unleashed three legends at nearly the same time with the updated Integra GS-R, the Prelude Si, and the Del Sol Si. By 1999, a new Civic Si landed with a 1.6L inline-4 making 160 horsepower at 8,000 rpm just like the NCE team intended. At this point, Honda’s VTEC system enjoyed a rabid fanbase and the hits just kept coming.
There was the mighty Honda S2000 roadster that stuffed 2 liters of displacement with 240 ferocious horsepower that could scream all the way up to an 8,900-rpm redline. Or how about the 2001 Acura Integra Type-R with a 1.8L four-pot making 195 hp with an 8,500-rpm redline?
The list goes on and on, but all these epic VTEC-powered Hondas shared the common trait of natural aspiration making the power output – and delivery – all the more remarkable. Since then, Honda has continued to refine its trademark VVT program including the use of forced induction and the later i-VTEC setup. This “intelligent” VTEC design blends traditional VTEC with variable timing control to great effect.
It makes you wonder, “Do all Honda’s have VTEC?”. The answer to that is “No” with a “But”. No, pre-1980s Hondas of course didn’t have VTEC and not every single modern Honda employs the technology including the latest Pilot SUV. While most of the latest Honda Civics use VTEC, certain trim lines like the Touring do not have VTEC engines. So, no, not all Honda’s have VTEC, BUT the best ones sure do.
