Quote Originally Posted by orly_andico View Post
what i've heard (but i'm no expert) is that i-VTEC is actually inferior to the older VTEC in terms of performance, it'sreally more geared for economy.

although i don't see why people get all worked up about VTEC in general. VTEC is primitive technology! having only a few discrete cam profiles. Porsche Variocam and BMW VANOS are both far more sophisticated.

or maybe Honda fanboys are just.. Honda fanboys.
Orly... i-VTEC is the next evolution of the VTEC3 & SOHC VTEC.

while the old VTEC only has cam-changing, the "i" adds variable cam-phasing to the intake valves.

with this it actually improves the powerband of the engine (notably torque output), giving the engine much better response even at low-rpm situations.

and yes... VTEC has just two cam profile. nothing spectactular. once the rpm hits 5000rpm (and assuming that there is enough oil pressure & a warm engine) it'll change to the more aggressive cam.

as for the comparison with the DOHC VTEC... well... the DOHC VTEC does have a higher hp output but at the expense of a gutless torque output plus it won't pass current & future emmission standards. I suspect that they toned down the previously very aggresive cam profile of the DOHC VTEC for use in the new R-series (with i-VTEC) engine.