<center> VTEC-E
</center>A novel implementation of VTEC in SOHC engines is the VTEC-E implementation (E for Economy). VTEC-E uses the principle of swirling to promote more efficient air-and-fuel mixing in the engine chambers. VTEC-E works by deactivating one intake valve. Examine the diagram below.
<table><tbody><tr> <td></td> <td>In the SOHC VTEC-E implementation, only one intake cam-lobe is implemented on the camshaft. Actually it is really a flat "ring". In operation this means the relevant rocker arm will not be activated causing the engine to effectively work in 12-valve mode. This promotes a swirl action during the intake cycle. VTEC is used to activate the inactive valve, making the engine work in 16-valve mode in more demanding and higher rpm conditions. Honda was able to implement air-fuel mixture ratios of more than 20:1 in VTEC-E during the 12-valve operating mode. The SOHC VTEC-E engined EG-series Civic ETi is able to return fuel consumptions of as good as 20km/litre or better!!
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SOHC VTEC implemented for power is often mistaken as SOHC VTEC-E which is implemented for economy. It is worthwhile to note that the 1.5l SOHC VTEC-E used in the JDM Honda Civic ETi produces 92ps. This is in fact less than that produced by the standard 1.5l SOHC engine's 100ps which uses dual Keihin side-draft carburettors. SOHC VTEC in the D15B produces 130ps. This is 30% more than the standard SOHC implementation !
http://asia.vtec.net/spfeature/vtecimpl/vtec1.html
(3rd August 2011)