SOHC vtec it used to be optimized in higher RPM. they share a common camshaft for intake and exhaust valves. then unlike the DOHC vtec it can only be used sa intake. i dont want to go technical...
SOHC vtec-e is opposite the vtec, it is optimized at lower RPM. only one of the two intake valves are open in a very small amount. may sliding pin lang ito to open the 2 valves.
kung similar ang SOHC vtec and SOHC vtec-e dapat mas matipid ito sa LXi version which has no vtec.