VTEC-E
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The earliest VTEC-E implementation is a variation of SOHC VTEC which is used to increase combustion efficiency at low RPM while maintaining the mid range performance of non-vtec engines. VTEC-E is the first version of VTEC to employ the use of roller rocker arms and because of that, it forgoes the need for having 3 intake lobes for actuating the two valves—two identical lobes for non-VTEC operation and one lobe for VTEC operation. Instead, there are two different intake cam profiles per cylinder—a very mild cam lobe with little lift and a normal cam lobe with moderate lift. Because of this, at low RPM, when VTEC is not engaged, one of the two intake valves is allowed to open only a very small amount due to the mild cam lobe, forcing most of the intake charge through the other open intake valve with the normal cam lobe. This induces swirl of the intake charge which improves air/fuel atomization in the cylinder and allows for a leaner fuel mixture to be used. As the engine's speed and load increase, both valves are needed to supply a sufficient mixture. When engaging VTEC mode, a pre-defined threshold for MPH (must be moving), RPM and load must be met before the computer actuates a solenoid which directs pressurized oil into a sliding pin, just like with the original VTEC. This sliding pin connects the intake rocker arm followers together so that now, both intake valves are now following the "normal" camshaft lobe instead of just one of them. When in VTEC, since the "normal" cam lobe has the same timing and lift as the intake cam lobes of the SOHC non-VTEC engines, both engines have identical performance in the upper powerband assuming everything else is the same.

With the later VTEC-E implementations, the only difference it has with the earlier VTEC-E is that the second "normal" cam profile has been replaced with a "wild" cam profile which is identical to the original VTEC "wild" cam profile. This in essence supersedes VTEC and the earlier VTEC-E implementations since the fuel and low RPM torque benefits of the earlier VTEC-E are combined with the high performance of the original VTEC.

3-Stage VTEC
Main article: 3-stage VTEC
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3-Stage VTEC is a version that employs three different cam profiles to control intake valve timing and lift. Due to this version of VTEC being designed around a SOHC valve head, space was limited and so VTEC can only modify the opening and closing of the intake valves. The low-end fuel economy improvements of VTEC-E and the performance of conventional VTEC are combined in this application. From idle to 2500-3000 RPM, depending on load conditions, one intake valve fully opens while the other opens just slightly, enough to prevent pooling of fuel behind the valve, also called 12-valve mode. This 12 Valve mode results in swirl of the intake charge which increases combustion efficiency, resulting in improved low end torque and better fuel economy. At 3000-5400 RPM, depending on load, one of the VTEC solenoids engages, which causes the second valve to lock onto the first valve's camshaft lobe. Also called 4-valve mode, this method resembles a normal engine operating mode and improves the mid-range power curve. At 5500-7000 RPM, the second VTEC solenoid engages (both solenoids now engaged) so that both intake valves are using a middle, third camshaft lobe. The third lobe is tuned for high-performance and provides peak power at the top end of the RPM range.