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Discussion Starter #1
From what is known the LS3 will use VVT technology, GM first started uses VVT technology with its new generation of 60 degree OHV V-6 engines the 3500 and 3900 VVT variations (3500 is also made in non VVT on the old block).

GM used a cam phaser on the camshaft which varied timing up to 40 degrees however because intake and exhaust lobes are tied to one camshaft they were moved at the same time.

A company has developed a special camshaft which has two camshafts built into one (a inner and outer camshaft) and its being used on the 2008 SRT-10 Viper. This system allows intake and exhaust valves to be adjusted separate from each other.

Will the LS3 use the simple cam phaser with both intake and exhaust being tied to eachother or will it use this new system?
 

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So if they go with the VVT... can we expect somewhat of a kick, similar to the Honda S2000 VTEC, at around 3500 RPM? Or would that not work with such a large engine?
 

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So if they go with the VVT... can we expect somewhat of a kick, similar to the Honda S2000 VTEC, at around 3500 RPM? Or would that not work with such a large engine?
you got the kick in honda's system because of how their V.V.T. system was designed. On Honda's two stage and three stage vtec system it literally works like a on off switch except more like a low high or in the case of the three stage system low mid then high. Honda's Vtec system actually has an extra lobe on the camshaft, for low it uses the two intake lobes however past a rpm level and with so much throttle the two intake valves switches from two separate lobes to one high lift lobe.

I am not sure about the current systems but Vtec only works on the intake side and is not continuously variable. However it incorporated both types of V.V.T. technology (cam phasing and cam changing). On G.M.'s system it only phases but it its constantly changing unlike the Vtec system and it varies a total of 40 degrees (advances 25 degrees and retards up to 15 degrees). So its smooth and you wouldn't be able to notice the change because its constantly changing. The end result is the broad torque curve of the S.B.C. V-8 engine is only going to get even broader.

I just hope that the new OHV VVT system gets used as it can also change overlap which will make the torque curve even broader. In theory you with this system you can make a LS7 motor that is completely emissions legal making around 500ft-lbs yet at the upper rpms makes over 700BHP. These kinds of VVT technologies removes the needed compromise that it takes in making a performance engine and making a performance engine easy on gas and clean through the camshaft. When Dodge made the new V-10 the only wanted an extra 50BHP however that VVT system gave them over 600BHP while burning cleaner then the older engine.
 

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defineately link this page to anyone who would call our engines primitive and say that HONDA was the inventor or variating valve timing. (wasnt GM the first to ever do it? i know not this system but something more primitive?)
 

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Discussion Starter #6
defineately link this page to anyone who would call our engines primitive and say that HONDA was the inventor or variating valve timing. (wasnt GM the first to ever do it? i know not this system but something more primitive?)
GM was the first to do a ton of things.

ABS system in the 50s (COrvette SS racer)
gas electric hybrid (developed in 1969)
GM had a earlier VVT system in the 70s but they werent the first.
 

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Thanks for the info, RoadKillz!
 
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