# CVTS/VVT



## SHIFTVAX (Jan 15, 2006)

What's the difference between CVTS and VVT and what makes one better than the other?


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## WoLfFaNgZ (Nov 8, 2004)

CVTS isnt that a transmission, Continuosly variable tansmission in the murano .And isnt VVt like hondas vtec?


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## V_Spec (Nov 2, 2005)

you mean , difference between CVTS and VTC? 

a said above CVT- continuosly variable transmision .
VTC - Variable valve Timing Control , is more like Toyota`s VVTi , it just adjust the timing at low RPM`s to get advantadge of torque , like moving in traffic for an example.


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## SHIFTVAX (Jan 15, 2006)

WoLfFaNgZ said:


> CVTS isnt that a transmission, Continuosly variable tansmission in the murano .And isnt VVt like hondas vtec?


I'm sorry I meant the difference between Continuous Variable Valve Timing and Variable Valve Timing Systems.


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## Char (Jun 16, 2005)

For the most part its just on how you say it... what you should really look at is the system itself, not the term. Take Honda's and Nissans VVT (using them as an example because they are two different systems.. and really the only I know ^-^ for example, Honda's V-TEC ingadges at a specific RPM depending on the motor and setup. It switches to larger lubes for the valves, effectivly changing their open and close times. Nissans.. as far as I know, is basically the same thing, but the computer is constantly adjusting it for the best at any given time, not just at a set RPM.

Anyone correct me as they wish.. this is just what Ive gathered from talking to people about VVT.


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## orochipower1118 (Jan 19, 2004)

Actually Honduhs V-Tec is is more like this:

when rpms hit a limit cheese is dropped and activates the mouse on a twin ball bering wheel. and makes the car go faster


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## stevja1 (Jan 25, 2004)

I've always wondered about that.... ^^^^^ I guess that's why they get the good mileage.

I think Honda's VTech has one switch point. I'll have to go look in my manual again for my Accord.

The Nissan VVL has two. Nissan's VVL doesn't continuously control the lift and duration of the valves. Each cam just has two sets of lobes. The intake cam usually gets switched first at a lower RPM, and then the exhaust cam switches a little later.

The only car I'm aware of that is fully variable is a new BMW motor that came out. I don't remember which model it'll be in, but I read about it in my Car and Driver a few months ago. It looked pretty cool.

Where did you see the CVTS?


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## SHIFTVAX (Jan 15, 2006)

stevja1 said:


> I've always wondered about that.... ^^^^^ I guess that's why they get the good mileage.
> 
> I think Honda's VTech has one switch point. I'll have to go look in my manual again for my Accord.
> 
> ...


I read in a Nissan booklet that the QR25 utilizes Contiuous Variable Valve Timing. Also the Valve cover for the 02-06' Spec V have the initials CVVTS. I don't think they have the VVL though like some SR20's.


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## Char (Jun 16, 2005)

Sorry I was a little wrong about Nissans.. it depends on the engine. From what I read about the SR20VE its just like Hondas but it changes the exhaust and intake lobes at different times, not at the same time like Hondas. As for the QR.. MAYBE it has the CVVT, Im not sure.


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## chris859 (Oct 20, 2005)

You guys are comparing completely different systems here... Variable valve timing is just that...it advances/retards the camshaft timing. While vtec, and vvl actualy use 2 seperate sets of lobes on the cams. Which allows the advantage of essentially having 2 different cam profiles in one engine. Long story short...vtec/vvl actually change the cam Lift, duration, and timing... While variable valve timing only changes camshaft timing - it doesn't affect lift on the cams at all.


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