Quote:
Originally Posted by darcane
Regardless of marketing, VTEC really only exists for fuel economy.
The same peak power can be made by just using the high cam profile at all times, rather than just at certain RPMs. VTEC simply allows an economical cam profile at low RPMs and high profile at high RPMs
The ricer kids don't like it when you point that out though...
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Not completely true. Running the aggressive lift/overlap cam at low revs would lower torque in that "below VTEC range" region...and also make the volumetric efficiency poor, thereby also decreasing FE. The only performance reason to remove VTEC switchover is if you are racing and are always going to be in the torque sweet spot or above on the "high lift" cam. High hp fast revving motors have also been known to have VTEC crossover issues because the oil pressures can not switch the cam fast enough causing wear to the valvetrain . BMW and basically every manufacturer has their version of variable valve lift or timing, and its usually a low rpm/high rpm performance benefit, with a FE benefit being an equally important effect.