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vvti gives you optimum valve actuation at lower and higher ends of your engne unlike vtec which only kicks in at high rpms= no low end torque. Prob honda/acura owners giving you this info. vvtiL is more advnced than vvti though.
 

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vvti is variable timing, on the intake cam on our cars

vvtli is variable timing with a switch over to a different set of cam lobes for variable lift (2 different sets of lobes) . its controlled hydraulically via oil pressure

vtec is variable lift, meaning 2 cam profiles

vtec-i is the same as vvtli in theory


i would check out http://www.howstuffworks.com for diagrams and such

-gte
 

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^what he said-

VVT-i (Variable Valve Timing w/ intelligence) controls TIMING on your intake valves

V-tec (Valve Timing and lift Electronic Control) has 2 different cam profiles, one low-rpm, one high-rpm, to change TIMING and LIFT, with a fixed engagement point.

VVTL-i (Variable Valve Timing and Lift w/ Intelligence (and vtec-i)is essentially a combination of the two, varying timing to optimize performance across the entire rpm range, but I believe the lift cam has a fixed engagement point still( for instance, 6000rpm in teh matrix).
 

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ltuned&boosted said:
vvti gives you optimum valve actuation at lower and higher ends of your engne unlike vtec which only kicks in at high rpms= no low end torque. Prob honda/acura owners giving you this info. vvtiL is more advnced than vvti though.
If comparing only the two, VTEC is superior.... don't forget that because it's two distinct cam profiles, they can independently be tuned for optimal high rpm operation AND low rpm operation in timing, lift, duration, and overlap. VVTi can only effect timing...although it has the advantage of doing so across the power band.
 
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