what is Vtech-E????
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Joined: Jul 2002
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From: Trackside with the smoking bee
Re: what is Vtech-E???? (Alpinestars21)
http://www.leecao.com/honda/vtec/sohcvtece.html
VTEC-E is a twist on the regular VTEC mechanism. Whereas VTEC's purpose can be more or less summarized as: extracting high RPM performance while maintaining smooth low RPM operation, VTEC-E can be summarized as: allow extremely lean fuel-air mixture at low RPMs in order to increase fuel economy. In other words, VTEC technology is used to optimize different ends of the RPM range in the two different implementations
First, some background information. Fuel is mixed with air and then combusted in cylinders to make torque. How much torque is generated is affected directly by how much and how well the fuel and air are mixed together. Less fuel and more air is called a "lean" mixture, the opposite is called a "rich" mixture. For low RPMs, a normal engine's intake charge velocity is low enough that the fuel and air are not mixed together very well. To make up for the sub-optimal mixing effect, a slightly rich fuel/air mixture (more fuel) is needed to maintain smooth operation. VTEC-E artificially increases the intake charge velocity, which creates a swirling effect inside the cylinder. This promotes a very good mixture of the fuel and air, thus allowing a lean fuel/air mixture to be used. The result of this is great fuel economy when running at low RPMs. Indeed, the current Civic HX, a 2400lb coupe, is capable of 37cty/44hwy fuel economy from a 115hp 1.6L VTEC-E engine. Now lets see how VTEC-E works in detail.
Unlike regular VTEC mechanisms, there aren't any extra cam lobes in a VTEC-E engine. So each pair of valves works off of exactly two cam lobes. Since VTEC-E merely increases the low RPM intake charge velocity, it is a mechanism that only affects the operation of the intake valves. VTEC-E is found only in SOHC engines due to its economical intentions. All this means that we only have to look at the two intake cam lobes and the associated rocker arms and valves in order to gain a full understanding of VTEC-E.
A non-VTEC-E engine normally has one single cam profile for the intake valves. A VTEC-E engine has two different intake cam profiles. At low RPMs, each intake valve works from its own intake cam profile. One of the intake cam profiles is very normal looking. The other one, however, is almost perfectly round, with just enough profile to it so that it pushes the valve open just enough to avoid pooling of fuel above the valve lip. Therefore at low RPM, only one intake valve is opening and closing. Most of the intake fuel and air are squeezed through this one valve, resulting in a good swirling effect in the cylinder. The swirling effect optimizes the fuel/air mixture, thus allowing a very lean mixture to be used.
As the RPMs increase, the demand for more fuel/air rises as well. Once a certain RPM is reached (approximately 2500RPM for the Civic HX), the one-intake-valve configuration starts to become a significant intake restriction. At this time, a solid pin is pushed through the two intake valve rocker arms, thus binding the two rocker arms into a single unit. This causes both intake valves to open and close according to the normal cam profile, while the almost-round cam profile is no longer used.
VTEC-E is some times confused to be just another high-RPM optimizing mechanism like other VTEC variants. And there is some truth to this: since only one intake valve is used at low RPMs, the one normal cam lobe is made to open that one valve slightly taller and for longer duration than if both intake valves are used. At higher RPMs, both valves follow this same cam lobe so they are both opened slightly taller and for longer duration. This results in a slight improvement in high RPM breathing compared to non-VTEC-E engines and thus slightly more power. This is evident by comparing the Civic DX and Civic HX engine. The two engines are essentially the same except for the VTEC-E in the Civic HX. But the Civic HX's VTEC-E mechanism results in 115hp, versus 106hp from the Civic DX. So the Civic HX has more power in addition to better fuel economy. But make no mistake, VTEC-E is designed with economy as the primary goal, not power output.
VTEC-E is a twist on the regular VTEC mechanism. Whereas VTEC's purpose can be more or less summarized as: extracting high RPM performance while maintaining smooth low RPM operation, VTEC-E can be summarized as: allow extremely lean fuel-air mixture at low RPMs in order to increase fuel economy. In other words, VTEC technology is used to optimize different ends of the RPM range in the two different implementations
First, some background information. Fuel is mixed with air and then combusted in cylinders to make torque. How much torque is generated is affected directly by how much and how well the fuel and air are mixed together. Less fuel and more air is called a "lean" mixture, the opposite is called a "rich" mixture. For low RPMs, a normal engine's intake charge velocity is low enough that the fuel and air are not mixed together very well. To make up for the sub-optimal mixing effect, a slightly rich fuel/air mixture (more fuel) is needed to maintain smooth operation. VTEC-E artificially increases the intake charge velocity, which creates a swirling effect inside the cylinder. This promotes a very good mixture of the fuel and air, thus allowing a lean fuel/air mixture to be used. The result of this is great fuel economy when running at low RPMs. Indeed, the current Civic HX, a 2400lb coupe, is capable of 37cty/44hwy fuel economy from a 115hp 1.6L VTEC-E engine. Now lets see how VTEC-E works in detail.
Unlike regular VTEC mechanisms, there aren't any extra cam lobes in a VTEC-E engine. So each pair of valves works off of exactly two cam lobes. Since VTEC-E merely increases the low RPM intake charge velocity, it is a mechanism that only affects the operation of the intake valves. VTEC-E is found only in SOHC engines due to its economical intentions. All this means that we only have to look at the two intake cam lobes and the associated rocker arms and valves in order to gain a full understanding of VTEC-E.
A non-VTEC-E engine normally has one single cam profile for the intake valves. A VTEC-E engine has two different intake cam profiles. At low RPMs, each intake valve works from its own intake cam profile. One of the intake cam profiles is very normal looking. The other one, however, is almost perfectly round, with just enough profile to it so that it pushes the valve open just enough to avoid pooling of fuel above the valve lip. Therefore at low RPM, only one intake valve is opening and closing. Most of the intake fuel and air are squeezed through this one valve, resulting in a good swirling effect in the cylinder. The swirling effect optimizes the fuel/air mixture, thus allowing a very lean mixture to be used.
As the RPMs increase, the demand for more fuel/air rises as well. Once a certain RPM is reached (approximately 2500RPM for the Civic HX), the one-intake-valve configuration starts to become a significant intake restriction. At this time, a solid pin is pushed through the two intake valve rocker arms, thus binding the two rocker arms into a single unit. This causes both intake valves to open and close according to the normal cam profile, while the almost-round cam profile is no longer used.
VTEC-E is some times confused to be just another high-RPM optimizing mechanism like other VTEC variants. And there is some truth to this: since only one intake valve is used at low RPMs, the one normal cam lobe is made to open that one valve slightly taller and for longer duration than if both intake valves are used. At higher RPMs, both valves follow this same cam lobe so they are both opened slightly taller and for longer duration. This results in a slight improvement in high RPM breathing compared to non-VTEC-E engines and thus slightly more power. This is evident by comparing the Civic DX and Civic HX engine. The two engines are essentially the same except for the VTEC-E in the Civic HX. But the Civic HX's VTEC-E mechanism results in 115hp, versus 106hp from the Civic DX. So the Civic HX has more power in addition to better fuel economy. But make no mistake, VTEC-E is designed with economy as the primary goal, not power output.
Member
Joined: May 2003
Posts: 2,980
Likes: 0
From: out in the farms, nj, USA
VTEC E is A economy motor .
it came in 92-95 VX hatches and 96-98 HX
they are fuel efficent like the crx hf good gas mileage and the ecus sucks. redline is low and by the time vtec kicks in your almost redlining. but if u want a slow car that gets u good gas mileage theyre good. if u use a vx head u can do a mini me
since its vtec. i think the cam might be smaller than a d16z6 or y8 but its till vtec. hope i could help
it came in 92-95 VX hatches and 96-98 HX
they are fuel efficent like the crx hf good gas mileage and the ecus sucks. redline is low and by the time vtec kicks in your almost redlining. but if u want a slow car that gets u good gas mileage theyre good. if u use a vx head u can do a mini me
since its vtec. i think the cam might be smaller than a d16z6 or y8 but its till vtec. hope i could help
Honda-Tech Member
Joined: Sep 2002
Posts: 3,033
Likes: 0
From: Richmond, VA, USA
Re: (thrty8street)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by thrty8street »</TD></TR><TR><TD CLASS="quote">does the "E" stand for economy?</TD></TR></TABLE>
yessir i believe so
yessir i believe so
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Re: what is Vtech-E???? (BauleyCivic)
Originally Posted by BauleyCivic
http://www.leecao.com/honda/vtec/sohcvtece.html
VTEC-E is a twist on the regular VTEC mechanism. Whereas VTEC's purpose can be more or less summarized as: extracting high RPM performance while maintaining smooth low RPM operation, VTEC-E can be summarized as: allow extremely lean fuel-air mixture at low RPMs in order to increase fuel economy. In other words, VTEC technology is used to optimize different ends of the RPM range in the two different implementations
First, some background information. Fuel is mixed with air and then combusted in cylinders to make torque. How much torque is generated is affected directly by how much and how well the fuel and air are mixed together. Less fuel and more air is called a "lean" mixture, the opposite is called a "rich" mixture. For low RPMs, a normal engine's intake charge velocity is low enough that the fuel and air are not mixed together very well. To make up for the sub-optimal mixing effect, a slightly rich fuel/air mixture (more fuel) is needed to maintain smooth operation. VTEC-E artificially increases the intake charge velocity, which creates a swirling effect inside the cylinder. This promotes a very good mixture of the fuel and air, thus allowing a lean fuel/air mixture to be used. The result of this is great fuel economy when running at low RPMs. Indeed, the current Civic HX, a 2400lb coupe, is capable of 37cty/44hwy fuel economy from a 115hp 1.6L VTEC-E engine. Now lets see how VTEC-E works in detail.
Unlike regular VTEC mechanisms, there aren't any extra cam lobes in a VTEC-E engine. So each pair of valves works off of exactly two cam lobes. Since VTEC-E merely increases the low RPM intake charge velocity, it is a mechanism that only affects the operation of the intake valves. VTEC-E is found only in SOHC engines due to its economical intentions. All this means that we only have to look at the two intake cam lobes and the associated rocker arms and valves in order to gain a full understanding of VTEC-E.
A non-VTEC-E engine normally has one single cam profile for the intake valves. A VTEC-E engine has two different intake cam profiles. At low RPMs, each intake valve works from its own intake cam profile. One of the intake cam profiles is very normal looking. The other one, however, is almost perfectly round, with just enough profile to it so that it pushes the valve open just enough to avoid pooling of fuel above the valve lip. Therefore at low RPM, only one intake valve is opening and closing. Most of the intake fuel and air are squeezed through this one valve, resulting in a good swirling effect in the cylinder. The swirling effect optimizes the fuel/air mixture, thus allowing a very lean mixture to be used.
As the RPMs increase, the demand for more fuel/air rises as well. Once a certain RPM is reached (approximately 2500RPM for the Civic HX), the one-intake-valve configuration starts to become a significant intake restriction. At this time, a solid pin is pushed through the two intake valve rocker arms, thus binding the two rocker arms into a single unit. This causes both intake valves to open and close according to the normal cam profile, while the almost-round cam profile is no longer used.
VTEC-E is some times confused to be just another high-RPM optimizing mechanism like other VTEC variants. And there is some truth to this: since only one intake valve is used at low RPMs, the one normal cam lobe is made to open that one valve slightly taller and for longer duration than if both intake valves are used. At higher RPMs, both valves follow this same cam lobe so they are both opened slightly taller and for longer duration. This results in a slight improvement in high RPM breathing compared to non-VTEC-E engines and thus slightly more power. This is evident by comparing the Civic DX and Civic HX engine. The two engines are essentially the same except for the VTEC-E in the Civic HX. But the Civic HX's VTEC-E mechanism results in 115hp, versus 106hp from the Civic DX. So the Civic HX has more power in addition to better fuel economy. But make no mistake, VTEC-E is designed with economy as the primary goal, not power output.
VTEC-E is a twist on the regular VTEC mechanism. Whereas VTEC's purpose can be more or less summarized as: extracting high RPM performance while maintaining smooth low RPM operation, VTEC-E can be summarized as: allow extremely lean fuel-air mixture at low RPMs in order to increase fuel economy. In other words, VTEC technology is used to optimize different ends of the RPM range in the two different implementations
First, some background information. Fuel is mixed with air and then combusted in cylinders to make torque. How much torque is generated is affected directly by how much and how well the fuel and air are mixed together. Less fuel and more air is called a "lean" mixture, the opposite is called a "rich" mixture. For low RPMs, a normal engine's intake charge velocity is low enough that the fuel and air are not mixed together very well. To make up for the sub-optimal mixing effect, a slightly rich fuel/air mixture (more fuel) is needed to maintain smooth operation. VTEC-E artificially increases the intake charge velocity, which creates a swirling effect inside the cylinder. This promotes a very good mixture of the fuel and air, thus allowing a lean fuel/air mixture to be used. The result of this is great fuel economy when running at low RPMs. Indeed, the current Civic HX, a 2400lb coupe, is capable of 37cty/44hwy fuel economy from a 115hp 1.6L VTEC-E engine. Now lets see how VTEC-E works in detail.
Unlike regular VTEC mechanisms, there aren't any extra cam lobes in a VTEC-E engine. So each pair of valves works off of exactly two cam lobes. Since VTEC-E merely increases the low RPM intake charge velocity, it is a mechanism that only affects the operation of the intake valves. VTEC-E is found only in SOHC engines due to its economical intentions. All this means that we only have to look at the two intake cam lobes and the associated rocker arms and valves in order to gain a full understanding of VTEC-E.
A non-VTEC-E engine normally has one single cam profile for the intake valves. A VTEC-E engine has two different intake cam profiles. At low RPMs, each intake valve works from its own intake cam profile. One of the intake cam profiles is very normal looking. The other one, however, is almost perfectly round, with just enough profile to it so that it pushes the valve open just enough to avoid pooling of fuel above the valve lip. Therefore at low RPM, only one intake valve is opening and closing. Most of the intake fuel and air are squeezed through this one valve, resulting in a good swirling effect in the cylinder. The swirling effect optimizes the fuel/air mixture, thus allowing a very lean mixture to be used.
As the RPMs increase, the demand for more fuel/air rises as well. Once a certain RPM is reached (approximately 2500RPM for the Civic HX), the one-intake-valve configuration starts to become a significant intake restriction. At this time, a solid pin is pushed through the two intake valve rocker arms, thus binding the two rocker arms into a single unit. This causes both intake valves to open and close according to the normal cam profile, while the almost-round cam profile is no longer used.
VTEC-E is some times confused to be just another high-RPM optimizing mechanism like other VTEC variants. And there is some truth to this: since only one intake valve is used at low RPMs, the one normal cam lobe is made to open that one valve slightly taller and for longer duration than if both intake valves are used. At higher RPMs, both valves follow this same cam lobe so they are both opened slightly taller and for longer duration. This results in a slight improvement in high RPM breathing compared to non-VTEC-E engines and thus slightly more power. This is evident by comparing the Civic DX and Civic HX engine. The two engines are essentially the same except for the VTEC-E in the Civic HX. But the Civic HX's VTEC-E mechanism results in 115hp, versus 106hp from the Civic DX. So the Civic HX has more power in addition to better fuel economy. But make no mistake, VTEC-E is designed with economy as the primary goal, not power output.
Honda-Tech Member
Joined: Oct 2003
Posts: 4,012
Likes: 1
From: Roanoke A.K.A. Redneckville,VA
Re: what is Vtech-E???? (Alpinestars21)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Alpinestars21 »</TD></TR><TR><TD CLASS="quote">what is vtech-E??? </TD></TR></TABLE>
is there some kind of new phone out?
chris
is there some kind of new phone out?
chris
Joined: Jun 2003
Posts: 54
Likes: 0
From: NY
OK, so maybe people don't read quite as much as BauleyCivic does.. (great info and post by the way). Finally someone that seems isn't basing their comments on hearsay.
the E is for Efficiency, not Economy.
I'll say no more on that just read in here and choose your side.. great info if you care to look at it objectively rather than that one A-hole that thought it was some kind of "Mine's better that Yours" Competition.
https://honda-tech.com/zerothread?id=101349
Flame away at me, I won't reply. I've neither the time nor desire.
good day.
the E is for Efficiency, not Economy.
I'll say no more on that just read in here and choose your side.. great info if you care to look at it objectively rather than that one A-hole that thought it was some kind of "Mine's better that Yours" Competition.
https://honda-tech.com/zerothread?id=101349
Flame away at me, I won't reply. I've neither the time nor desire.
good day.
Joined: Dec 2002
Posts: 1,506
Likes: 1
From: manchester, nh, us
Re: (lsintegra95)
my old d15z1 VX engine had 350K miles and ran smooth as **** before i pulled it out. and i know 2 others with over 280k where i live. i loved it while i had it, but i dont miss it. 
to Honda for designing a kick *** fuel efficient engine
to Honda for designing a kick *** fuel efficient engine
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