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Ever heard your fanatic Honda sidekick say, “VTEC just kicked in! ” and not had a clue what they’re talking about? At this level, VTEC nearly may seem like one of those memes that’s been parroted so many times that nobody remembers what it intends. Let’s explore.
What exactly is VTEC? As an acronym, it stands for Variable Valve Timing and Lift Electronic Control. Perhaps Honda should have called it VVTaLEC, but that’s not nearly as catchy, is it? Functionally, it’s a technology that enables an engine to breathe more freely at higher rpm to grow performance.
Engine Lessons
An internal combustion engine is effectively a very complicated air pump. The more air it can suck in and force out, the more ga it can mix with that breath and “the worlds biggest” explosions( read: more ability) it can make. Air enters and exits the cylinder through valves on the intake and exhaust sides. Those valves is regulated by revolving camshafts with lobes that push the valves open and valve springs that violence them closed again.
Altering the altitude and width of the lobes on the camshaft will change how long the valves open and how far they open. Larger, longer valve openings signify more airflow and more influence. So why isn’t every engine fitted with big cams? Problem is, an aggressive cam is inefficient at low-spirited rpm because it prioritizes the volume of breath rather than its pressure. Smaller amounts of breath moving at a higher velocity( as a result of shorter, smaller valve openings) mix more evenly with the fuel and burn more efficiently.
To solve the problem, Honda developed VTEC to enable its locomotives to run a lower, more efficient cam profile at lower rpm and a higher, more aggressive cam profile higher in the rev range to maximize power. At a certain rpm, hydraulic pressure in the engine would reach a point at which it would actuate a selector pin, involving the higher cam and enabling maximum performance.
Drive VTEC, Love VTEC
VTEC made its North American debut in the 3.0 -liter V-6 mounted in the middle of the first-generation 1991 Acura NSX. By 1999, though, Honda’s trademark tech had percolated down all the way down to the humble( and much more accessible) Civic. Specifically, the Civic Si.
Honda was kind enough to lend us a spotless, bone-stock 1999 Civic Si in Electron Blue for Radwood L.A ., and it was the perfect behavior to refamiliarize myself with the engine technology that birthed an whole generation of Honda followers. The Si is powered by Honda’s B1 6A2 engine, a 1.6 -liter inline-four that develops 160 hp at 7,600 rpm and 111 lb-ft of torque. Sure, the 1.5 -liter turbo-four in the current-gen Civic attains better amounts than those, but to achieve 100 hp per liter from a naturally aspirated locomotive is a monumental achievement that few vehicles achieve today and even less did 20 years ago.
It’s a wonderful little car to drive. Curb weight is a featherlight 2,600 pounds, and visibility is panoramically marvelous thanks to slim mainstays, big windows, and a low-toned hood. But the characteristic that defines this 20 -year-old Civic’s driving experience is without question the VTEC cam changeover that takes place when the tachometer swings past 5,600 rpm.
Exploring the last 2,500 rpm of this engine is like poking at a dormant volcano asking to explode. It’s as if you detected another 3 inches of gas pedal travel and could push the pedal straight-out through the floorboard. A B1 6A2 dyno map demonstrates exactly how drastic the changeover can be.
Even a week later, I’m still “ve been thinking about” this locomotive. How docile and pedestrian it felt trundling around my vicinity between stop signs but how raucous and mechanical and stimulated it was once I traversed that threshold into the higher reaches of its powerband. And what’s special about this automobile is that the power is accessible enough that you can use it just about anywhere. It’s possible to experience VTEC in first and second gear below most roadway speeding limits. If you drive like I do, everywhere you go you’ll be revving this locomotive to the moon and grinning ear to ear.
All hail VTEC. Long may it reign.
The post What is VTEC? Featuring a 1,100 -Mile 1999 Honda Civic Si showed first on MotorTrend.
Read more: motortrend.com
