The variable valve timing (VVT) war in automotive industries back in 1990's created quite a number of decent engine from different manufacturer with their respective names, designs and claims. Generally VVT split into 3 categories:- cam phasing (valve timing)
- cam phasing + switching (valve timing and lift)
But despite those variable-names-given, they actually are using more or less the same mechanism. Example; B16A VTEC has 3-lobe camshaft while 4G92 MIVEC had only 2, but cam engagement method for both system are same; oil pressure-triggered.
Nissan introduced this infamous Pulsar VZ-R equipped with Neo VVL SR16 engines; a 1.6L 16-valve 4-banger that rev to 8000rpm and manages to deliver 173 hp (129 kW) and, it came with blue coloured cover rocker. The tri-lobe camshafts design is very similar to the one found in Honda VTEC. One difference is that NEO VVL engages the intake and exhaust cams independently. The intake cam engages somewhere around 5100rpm and the exhaust cam engages at 6500rpm.
From 1997 to 1998, Nissan produced 500 limited edition SR16VE N1 engines which came with the sportier VZ-R N1. They had further upgraded camshafts (high cam duration up from 280 to 288), ported head from factory, increased engine compression, enlarged intake manifold, 8 (yes, eight) injectors and a larger 70 mm throttle body. These engines made a killer 197 hp (147 kW) and tagged with red coloured cover rocker. One thing really caught my intention is, these engines were chain-driven. It's rare to see one especially in a 1.6L Japenese engine which most of it were belt-driven at that time. This minimized the maintainance cost as the chain lifespan is way much longer than belt; period.
SR16 VVL camshafts
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