So this is a feature on this new engine, but how does it work? Is it controled manually or electronicly and or automaticly? do u get more horses/torq? do u have to change to premium gas if u tune it up? any info would be great, thanks

I have a 3.0 VVT Mazda 6 and the way they described it to me is the valves are adjusted electronically to balance hp and torque thru the powerband under current driving conditions. One nice thing you also get with VVt is the ability to do traction control with a 5 speed, it actualy links to sensors so when a tire is sprinning it adjust the valve time to reduce the torque untill the tre stops spinning and gains traction again.

ahh thanks

I have a 3.0 VVT Mazda 6 and the way they described it to me is the valves are adjusted electronically to balance hp and torque thru the powerband under current driving conditions. One nice thing you also get with VVt is the ability to do traction control with a 5 speed, it actualy links to sensors so when a tire is sprinning it adjust the valve time to reduce the torque untill the tre stops spinning and gains traction again.

sounds about right. But a car does not need VVT to have traction control. Any ECM can be made to reduce power to a spining tire.

sounds about right. But a car does not need VVT to have traction control. Any ECM can be made to reduce power to a spining tire.

Yes that is correct as for a ECM. But one really nice thing about VVT is it reduces torque only not hp.

There is a replacement for displacement and it's called high compression and piston speed, why do you think that Ferrari and McLaren have 6.0-7.0 L engines that have 10- 12 cylinders?... do the math that’s 500 cc’s per cylinder, what’s 2.4 divided by 4? Well there you have it. Unless of course the best automotive manufacturers in the world are being proven wrong by ??Grumman?? Not likely

I was into talk to a chev dealer in NS Canada and they didn't seem to know anything about the 2.4L SS, does anyone know if it's only released in the US?

I was into talk to a chev dealer in NS Canada and they didn't seem to know anything about the 2.4L SS, does anyone know if it's only released in the US?

Too many dealers are clueless. Canada in paticular--they are the last to know anything. Its coming here for sure so you'll have to wait a bit.

yeah the dealers probably wont know about it till they notice the "2.4" on the window stickers.

Yes that is correct as for a ECM. But one really nice thing about VVT is it reduces torque only not hp.

Reduce torque but not horsepower? The equation for horsepower is based on torque.
So if you drop the amount of torque you are going to drop the amount of horsepower.

HP = RPM * (TQ/5252)

Here goes nothing...

A camshaft is usually matched to an operating RPM range...the RPM range of which a cam works most efficiently is basically determined by 3 things - lift, duration, and overlap. Generally speaking, the more lift, duration, and overlap a cam has the higher the RPM range a cam can efficiently work...of course the compromise is it isn't as efficient at lower RPMs. Now wouldn't it be nice if you could change 1 or all 3 as the RPMs increase. That's were VVT comes in. Different methods are used by different manufacturers (different methods are used between different engines also) so I won't go into how here...that would take too much space.

Exactly. VVT is like having a constantly varying camshaft based on the current RPM.
It is a very good technology that really helps give engines more power across all the
powerband. You get the best of both worlds, low end torque and high end horspower.

I believe the new Mustangs use VVT now, or at least some variation of it.
VTEC has graduated beyond "imports" and is now invading US products. :)

yeah the dealers probably wont know about it till they notice the "2.4" on the window stickers.

ahhah thats Hilarious, I have no idea why they even get hired. Well thanks it’s really good to know that there will be a 2.4L SS they have so much more potential, especially once you get the twin turbos on it

im excited for their release!!

ahh, screw boost. I'll take a 2.4 and polish it up nicely.you can add more horses (even more importainly torq) with out slaping turbos on it. its all the little things like ignition and underpullies. thanks for the info on VVT guys! it sounds nice,

VVT as used on the LE5 will be an electronically controlled hydraulically actuated(engine oil) system that can vary camshaft timing of the intake AND exhaust cams helical spline actuators bolt to the cams and the timing sprockets are integrated into the actuator.. as oil is forced into or exhausted out of the actuator it will move on its splines changing the position of the cam relative to the crankshaft......the most worthwhile purpose of this is to increase efficiency and therefore hp...also emissions are reduced and higher levels of hp can be reached with little or no sacrifice to idle quality or driveability....when the exhaust cam is retarded the exhasut valve will stay open on the intake stroke scavenging exhaust gas into the cylinder to produce similar results as the digital EGR valve system does....when the intake cam is advanced the intake cam will start to open during the exhaust stroke allowing fresh air into the exhaust stream and performing a similar function to Secondary Air Injection Reaction systems.

I was into talk to a chev dealer in NS Canada and they didn't seem to know anything about the 2.4L SS, does anyone know if it's only released in the US?

Considering its not even out yet why would they know or want to know. They would be stupid to tell you to come back in 3 months to get the new model. The 2.4L SS is no more than a "known myth" right now that emans it will happen but its not technically for sure yet

VVT as used on the LE5 will be an electronically controlled hydraulically actuated(engine oil) system that can vary camshaft timing of the intake AND exhaust cams helical spline actuators bolt to the cams and the timing sprockets are integrated into the actuator.. as oil is forced into or exhausted out of the actuator it will move on its splines changing the position of the cam relative to the crankshaft......the most worthwhile purpose of this is to increase efficiency and therefore hp...also emissions are reduced and higher levels of hp can be reached with little or no sacrifice to idle quality or driveability....when the exhaust cam is retarded the exhasut valve will stay open on the intake stroke scavenging exhaust gas into the cylinder to produce similar results as the digital EGR valve system does....when the intake cam is advanced the intake cam will start to open during the exhaust stroke allowing fresh air into the exhaust stream and performing a similar function to Secondary Air Injection Reaction systems.
ok........ I got something out of this.....lower emmisions, not as harsh on the environment. works for me cus i'm an environmentalist.
no, i get most of it, its auto controled: initiated electronicly and actually carried out mechanicly, with oil.
thanks man! :cool:

VVT as used on the LE5 will be an electronically controlled hydraulically actuated(engine oil) system that can vary camshaft timing of the intake AND exhaust cams helical spline actuators bolt to the cams and the timing sprockets are integrated into the actuator.. as oil is forced into or exhausted out of the actuator it will move on its splines changing the position of the cam relative to the crankshaft......the most worthwhile purpose of this is to increase efficiency and therefore hp...also emissions are reduced and higher levels of hp can be reached with little or no sacrifice to idle quality or driveability....when the exhaust cam is retarded the exhasut valve will stay open on the intake stroke scavenging exhaust gas into the cylinder to produce similar results as the digital EGR valve system does....when the intake cam is advanced the intake cam will start to open during the exhaust stroke allowing fresh air into the exhaust stream and performing a similar function to Secondary Air Injection Reaction systems.




thank you im glad someone has the ability to answer these questions accurately
how long you been mr goodwrench?

No problem guys :-D

Solkacs, I have been an ASE certified technician for nearly 10 years, working almost exclusively on GM vehicles the entire time, I have been at my current employer(a South Jersey Chevy dealer) for three years as of August. :cssNET:

fuck u
what the? why are u mad? :confused:

alright I really have no clue how VVT works but I own a 2008 sport 2.4L with VVT and have heard/ wondered if there was anyway to control when VVT kicks in to produce more hp.... only reason why i'm even asking is because apparently it's controlled electronically and that makes me think that some kind of controller could be used to do this. maybe i'm wrong

No way did you just bump this thread. Here's your answer: http://en.wikipedia.org/wiki/Variable_valve_timing and http://auto.howstuffworks.com/camshaft2.htm

No way did you just bump this thread. Here's your answer: http://en.wikipedia.org/wiki/Variable_valve_timing and http://auto.howstuffworks.com/camshaft2.htm

Bro listen the last post on this thread was 4 years ago. Some people with some good knowledge about this posted here so don't give me shit.

To answer your question... VVT doesn't "kick in". It's not VTEC. Read up in those links I posted, it'll take you 5 min and you'll have a vastly greater understanding

To answer your question... VVT doesn't "kick in". It's not VTEC. Read up in those links I posted, it'll take you 5 min and you'll have a vastly greater understanding

Thanks, chief. Fuck you.

Thanks, chief. Fuck you.

dont bitch at him for helping you. read it and learn, or dont and call him names... take a guess which one benefits you.

lol I answered his question and posted links going into greater detail. lol what a moron

its cool acey... guess he just wanted to start something lol...

let his VVT kick in... and ill tell my friend to sell him a VVT controller so it kicks in EARLIER YO!!!

lol

VVT is the next best thing to having valves that are individually actuated.

To answer your question... VVT doesn't "kick in". It's not VTEC. Read up in those links I posted, it'll take you 5 min and you'll have a vastly greater understanding

If he had actually read what you posted he would have known that. :lol: I learned that unlike VVT, VTEC switches between two different cam lobes depending on the RPM hence the "kick". Also i-VTEC can alter intake timing continuously in addition to what VTEC already does. I could go on and on about what I learned.

That's what you get for helping people on this board. But I still love yall

That's what you get for helping people on this board. But I still love yall

homo



:lol:

homo



:lol:

Love you. :)

so this is like the domesticated V-Tec? lol

so this is like the domesticated V-Tec? lol

no its the wanna be version of vtec :lol:

no its the wanna be version of vtec :lol:

except its better?

so its the improved VTEC

no, honda had it first so its the wanna be version like I said. lol

No way did you just bump this thread. Here's your answer: http://en.wikipedia.org/wiki/Variable_valve_timing and http://auto.howstuffworks.com/camshaft2.htm

i mean what am i supposed to say to this? tellin me not to bump the thread when the last post was 4 years ago. i mean common man you know you were being a little bitch about it. thanks for the info though.

no, honda had it first so its the wanna be version like I said. lol

IIRC, GM invented VTEC, and sold the patent to Honda, who actually started using it on their cars. soo....GM had it first :cssNET:

wiki vvt and i think it was volvo or a european car maker
who intented it, caddy used it but not much of a success.
google and wiki is your friend. honda just made it
famus.

IIRC, GM invented VTEC, and sold the patent to Honda, who actually started using it on their cars. soo....GM had it first :cssNET:

that's pretty crazy... def didn't know that. that's awesome.

IIRC, GM invented VTEC, and sold the patent to Honda, who actually started using it on their cars. soo....GM had it first :cssNET:

Thats interesting...I didnt know that either. I'm curious to know where you got that info from because everywhere I have read on the internet always displays info along these lines...and its weird that this search turned up nothing about GM...

VTEC (Variable Valve Timing and Lift Electronic Control) is a valvetrain system developed by Honda to improve the volumetric efficiency of a four-stroke internal combustion engine. This system uses two camshaft profiles and electronically selects between the profiles. It was invented by Honda R&D engineer Ikuo Kajitani.[1] It can be said that VTEC, the original Honda variable valve control system, originated from REV (Revolution-modulated valve control) introduced on the CBR400 in 1983 known as HYPER VT EC.[2] VTEC was the first system of its kind, though other variable valve timing and lift control systems have been produced by other manufacturers (MIVEC from Mitsubishi, VVTL-i from Toyota, VarioCam Plus from Porsche, VVL from Nissan, etc).

Thats interesting...I didnt know that either. I'm curious to know where you got that info from because everywhere I have read on the internet always displays info along these lines...and its weird that this search turned up nothing about GM...

VTEC (Variable Valve Timing and Lift Electronic Control) is a valvetrain system developed by Honda to improve the volumetric efficiency of a four-stroke internal combustion engine. This system uses two camshaft profiles and electronically selects between the profiles. It was invented by Honda R&D engineer Ikuo Kajitani.[1] It can be said that VTEC, the original Honda variable valve control system, originated from REV (Revolution-modulated valve control) introduced on the CBR400 in 1983 known as HYPER VT EC.[2] VTEC was the first system of its kind, though other variable valve timing and lift control systems have been produced by other manufacturers (MIVEC from Mitsubishi, VVTL-i from Toyota, VarioCam Plus from Porsche, VVL from Nissan, etc).

got it on here from some technical guru. although...after doing a little searching..looks like he was wrong?

o well...w/e

Fiat was the first auto manufacturer to patent a functional automotive variable valve timing system which included variable lift. Developed by Giovanni Torazza in the late 1960s, the system used hydraulic pressure to vary the fulcrum of the cam followers (US Patent 3,641,988). The hydraulic pressure changed according to engine speed and intake pressure. The typical opening variation was 37%.

In September 1975, General Motors (GM) patented a system intended to vary valve lift. GM was interested in throttling the intake valves in order to reduce emissions. This was done by minimizing the amount of lift at low load to keep the intake velocity higher, thereby atomizing the intake charge. GM encountered problems running at very low lift, and abandoned the project.

Alfa Romeo was the first manufacturer to use a variable valve timing system in production cars (US Patent 4,231,330). The 1980 Alfa Romeo Spider 2.0 L had a mechanical VVT system in SPICA fuel injected cars sold in the United States. Later this was also used in the 1983 Alfetta 2.0 Quadrifoglio Oro models as well as other cars. The system was engineered by Ing Giampaolo Garcea in the 1970s.[2]

Honda's REV motorcycle engine employed on the Japanese market-only Honda CBR400F in 1983 provided a technology base for VTEC.

Fiat was the first auto manufacturer to patent a functional automotive variable valve timing system which included variable lift. Developed by Giovanni Torazza in the late 1960s, the system used hydraulic pressure to vary the fulcrum of the cam followers (US Patent 3,641,988). The hydraulic pressure changed according to engine speed and intake pressure. The typical opening variation was 37%.

In September 1975, General Motors (GM) patented a system intended to vary valve lift. GM was interested in throttling the intake valves in order to reduce emissions. This was done by minimizing the amount of lift at low load to keep the intake velocity higher, thereby atomizing the intake charge. GM encountered problems running at very low lift, and abandoned the project.

Alfa Romeo was the first manufacturer to use a variable valve timing system in production cars (US Patent 4,231,330). The 1980 Alfa Romeo Spider 2.0 L had a mechanical VVT system in SPICA fuel injected cars sold in the United States. Later this was also used in the 1983 Alfetta 2.0 Quadrifoglio Oro models as well as other cars. The system was engineered by Ing Giampaolo Garcea in the 1970s.[2]

Honda's REV motorcycle engine employed on the Japanese market-only Honda CBR400F in 1983 provided a technology base for VTEC.

hmm thats very interesting so GM was headed in the right direction but wasnt successful with their designing of it. If alfa romeo had their system engineered in the 1970's I wonder who actually invented the technology...

hmm thats very interesting so GM was headed in the right direction but wasnt successful with their designing of it. If alfa romeo had their system engineered in the 1970's I wonder who actually invented the technology...

...Fiat

its the first sentence

vtec is 2 sets of cam lobes hydraulically actuated at 4000 rpm's. it's a higher lift and more aggressive timing. vvt is a hydraulically actuated cam timing control. doesn't change lift.

...Fiat

its the first sentence



yeah you're right about that but fiat isnt GM and honda may not have invented it but honda apparently made it simpler and was one of the first to prooduce it on ecomony cars and every other car manufacturer out there just about has tried to copy it by designing something almost exactly like it. oh well

vtec is 2 sets of cam lobes hydraulically actuated at 4000 rpm's. it's a higher lift and more aggressive timing. vvt is a hydraulically actuated cam timing control. doesn't change lift.

Yeah the actuation RPM varies depending on the motor... I think on older Si's it used to be like 5800

Acually all in all BMW held design vtec first n vvti is nothing live vtec it's more like venos I guess it uses cam phasing to advance or retard a cam hense why we do not have a egr

right it leaves the exhaust valve open for a split second during the intake stroke serving the same purpose as an egr system

Yeah the actuation RPM varies depending on the motor... I think on older Si's it used to be like 5800

I think the newer ones are at either 5600 or 5800 too.

my bad, I should have said that.

The VVT in the ecotec does not affect valve lift or duration -- these stay the same. What the VVT does do is change the camshaft relationship with the crankshaft. Think of it as an automatic sprocket adjuster -- the cams move back or forward to advance or retard up to 60 degrees at the sprocket. In technical terms it changes the intake and exhaust camshafts' lobe separation.