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vvt vs vct?

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Old 04-22-2009, 12:27 PM
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Default vvt vs vct?

whats the difference between these two designations?
 
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Old 04-22-2009, 12:40 PM
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VCT Variable Cam Timing: Valve controls oil flow to unique camshaft sprocket with a phasing device that advances/retards timing according to oil volume provided by control valve.

VVT Variable Valve Timing: Increased engine breathing through the entire rpm range by varying points which valves open/close in conjunction with piston position.
 

Last edited by bountyhunter; 04-22-2009 at 02:31 PM.
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Old 04-22-2009, 01:01 PM
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when going over window stickers--I see some come with the vct engine while others come with a vvt engine--both 5.7 liter v8 mds

unusual--is it a sport package thing?

what would be the pros and cons of each
 
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Old 04-22-2009, 01:08 PM
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VCT has more power and torque, and is supposed to be more fuel efficient. VCT is also more complex and costs more to build.
I heard that they will discontinue VCT because of the later. So I guess the cons of VCT may be parts scarcity.
 

Last edited by mopowar; 04-22-2009 at 01:11 PM.
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Old 04-22-2009, 01:18 PM
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does the vct still pump out 390 or more?

mopowar---your sport has the vct?
 

Last edited by siegelreptiles; 04-22-2009 at 01:22 PM.
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Old 04-22-2009, 01:55 PM
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Yes, I have the VCT. From everything I have read the VCT will put out more HP than the VVT.
 
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Old 04-22-2009, 04:25 PM
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There is no difference in vct and vvt i called dodge and talked to two different tects they said the change is on window sticker only so if you got a vct or vvt they are exactly the same
 
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Old 04-22-2009, 04:40 PM
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I guess that does make sense. Everything I have read on it points to two different mechanisms, one used for vvt and one for vct, but this would essentially mean that they would have to turn out two different motors. If there is in fact no difference, then, again from what I've read, I think what they are calling vvt is actually vct.
I did read somewhere that they will be doing away with vct in favor of vvt to cut manufacturing cost.
 
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Old 04-22-2009, 04:51 PM
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If you look here:
http://www.taylorparkermotor.com/new...d6e551f3955cd0

About halfway down the page under Options it lists:

Engine: 5.7L V8 HEMI MDS VCT (Discontinued)
Engine: 5.7L V8 HEMI MDS VVT

So maybe they are turning out two different motors after all, and the Dodge cutomer service guy was yanking your chain.

What I read before said something along the lines of; If you can find a Ram with VCT
you ought to grab it.
 
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Old 04-22-2009, 09:27 PM
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Interesting, saved my window sticker in the glove box, looked at it tonight and says : VCT. Build date is 12/08.
 



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