Honda Car Forum

what is the technology behind V-TEC HONDA ENGINES?

Variable valve Timing and Electronic lift Control. The engine design uses two sets of cams, one for low RPMs and one for high RPMs. When in higher RPMS, the longer lobs are used to open the intake for longer, as it is known that at higher RPMs a better engine response is given, but at lower RPMs it is counter productive, thus the other lower RPM set. The high RPM set is engaged by the computer system, in effect changing the valve timing on the fly. Basically, when you hit a higher RPM your response is similar to a turbo boost.

http://asia.vtec.net/article/ivtec/

I think it is something to do with the improved fuel flow and valve gears.

Vtech which stands for variable valve timing is where the ECU controls the operation of the valves and opens them all the way at a certain RPM this creates a power band in the performance of the motor.

Variable valve timing. A cam lobe changes the effective profile of the cam at a certain rpm, to provide greater power at higher rpm. Nowdays, both intake and exhaust valves are variable.

VTEC. Four letters that practically started a revolution. To Honda's engineers, it means Variable Valve Timing and Lift Electronic Control. But for some of us it sparks thoughts of many other things: space age-sounding technology, the unmistakable sound of a VTEC motor revving up, the innovation that yielded naturally aspirated engines 100 hp/liter before any other manufacturer--the very technology that arguably could have launched the sport compact scene in the early-'90s. But there's quite a bit more to it than that. VTEC innovations are evolving and constantly leaving their mark in the automotive world.































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