Originally Posted by Oildudeny
I miss the old vtec where you knew vtec was singing. Vvt just doesn't have that in your face kick.
Off topic a little:
That's because VVT simply changes cam timing and not lift or duration. Those of us who hot-rodded engines for years understand the true capability of "big cams" vs. re-timed emissions cams.
For example, it was common for 1800cc engines to produce a real world 250HP. Such as variants of the Cosworth BD engines. These were fire breathing monsters, with some righteous cam profiles. Fast forward to Honda's VTEC, and the 2000cc/240 HP engine was not far off the mark. It took aggressive cam profiles to make that happen, not VVT.
The BD series of engine, designed in the late 1960's should look familiar to many of us, as it's the basis for many modern designs.
FYI, Ford's VVT has a strong tendency to fail with the use of uber thin oils. Here in South Florida, Ford tech have discovered that higher viscosities result in longer cam phaser life. The speculation is that the thin oils and particulates wear the phasers our more rapidly, leading to an annoying knock.
I use M1 10W-30 and 10W-40 (depending on season) in my 5.4L Ford V8, 120,000 miles, and no phaser knock. I've done better than my neighbors, many of whom have had phasers replaced at least once, sometimes twice.