This is pretty neat:
Lots of oil passages in that setup!
Lots of oil passages in that setup!
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Variable duration camshaft system
- Thread starter robertcope
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I have seen all kinds of so called advancements in engine design/construction over the last 30 years, usually involving increased complexity and manufacturing costs, but I have experienced very little benefits, if any. I recently switched from a 2006 GM sedan to a 2016 Hyundai hatchback with all kinds of so called "advancements" yet I see no benefits. Perhaps it runs cleaner. I won't be rushing out to get one of these engines.
I've wondered when this technology would make it's way onto production cars. They've been able to adjust valve timing for a long time now, it was only a matter of time before someone came out with adjust valve duration. I didn't know Hyundai developed this.
Very cool. Seems a lot less complex and consequently should be more reliable vs say the BMW Valvtronic system. Just change your oil !
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This is neat. The efforts to keep ICE valid is something most gear heads will appreciate. I do expect that this new innovation will make oil selection and change frequency super important.
I thought this is what the Fiat Multiair system does (along with variable lift)?
Originally Posted by Surestick
I thought this is what the Fiat Multiair system does (along with variable lift)?
Agreed...with the MultiAir technology, their engines don't even have a throttle plate, airflow is controlled entirely by the intake valves.
https://www.wardsauto.com/news-analysis/fiat-breathing-easy-multiair
This is not new...Fiat introduced it in production engines in 2009
I thought this is what the Fiat Multiair system does (along with variable lift)?
Agreed...with the MultiAir technology, their engines don't even have a throttle plate, airflow is controlled entirely by the intake valves.
https://www.wardsauto.com/news-analysis/fiat-breathing-easy-multiair
This is not new...Fiat introduced it in production engines in 2009
At this rate there will have to be a separate discrete lubrication system separate from the carbon-fouled crankcase oil to keep these
cam phasing systems clean enough to operate correctly through the warranty period. : l
Not saying that is good or bad but that's where it's heading.
cam phasing systems clean enough to operate correctly through the warranty period. : l
Not saying that is good or bad but that's where it's heading.
They have been around for a long time. Since VTEC / Vanos / VVTI / whatever from 25 years ago.
The problem is always a tradeoff between cost / reliability / fuel economy. This is what brings your engine from the 25mpg in the 90s to the 35mpg today. DI and 6 speed auto brings it up further from 35mpg to 40mpg.
The problem is always a tradeoff between cost / reliability / fuel economy. This is what brings your engine from the 25mpg in the 90s to the 35mpg today. DI and 6 speed auto brings it up further from 35mpg to 40mpg.
VTEC/Vanos/VVTI/MultiAir don't do this. They do timing and lift, which is different than duration. This is explained in the video.
Originally Posted by PandaBear
They have been around for a long time. Since VTEC / Vanos / VVTI / whatever from 25 years ago.
The problem is always a tradeoff between cost / reliability / fuel economy. This is what brings your engine from the 25mpg in the 90s to the 35mpg today. DI and 6 speed auto brings it up further from 35mpg to 40mpg.
Originally Posted by robertcope
VTEC/Vanos/VVTI/MultiAir don't do this. They do timing and lift, which is different than duration. This is explained in the video.
BMW has been doing it for over a decade. They call it Valvetronic and it is integrated with VANOS. It's why BMW turbo engines have very low lag and higher low speed efficiency.
The BMW system is rather complex (no surprise there) and the typical failure is lost gear teeth on what is called the eccentric shaft or failure of the eccentric motor itself (The Hyundai system is mounted horizontally). The eccentric shaft runs about $800.
They have been around for a long time. Since VTEC / Vanos / VVTI / whatever from 25 years ago.
The problem is always a tradeoff between cost / reliability / fuel economy. This is what brings your engine from the 25mpg in the 90s to the 35mpg today. DI and 6 speed auto brings it up further from 35mpg to 40mpg.
Originally Posted by robertcope
VTEC/Vanos/VVTI/MultiAir don't do this. They do timing and lift, which is different than duration. This is explained in the video.
BMW has been doing it for over a decade. They call it Valvetronic and it is integrated with VANOS. It's why BMW turbo engines have very low lag and higher low speed efficiency.
The BMW system is rather complex (no surprise there) and the typical failure is lost gear teeth on what is called the eccentric shaft or failure of the eccentric motor itself (The Hyundai system is mounted horizontally). The eccentric shaft runs about $800.
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Originally Posted by robertcope
VTEC/Vanos/VVTI/MultiAir don't do this. They do timing and lift, which is different than duration. This is explained in the video.
I don't think you have taken the time to actually learn about MultiAir. It has complete control over timing, lift, and duration. To the point THERE IS NO THROTTLE.
The system uses electro-hydraulic valve actuators; a solenoid energized with each rotation of the camshaft regulates the amount of oil sent to the actuator, which controls the amount of lift from completely closed to completely open. Rather than having a limited number of positions between open and closed, there is infinite variation over the opening of the intake valves.
Unlike competing systems, MultiAir allows for each individual cylinder's valves to be adjusted independently, for faster responses.
Valve timing is also adjusted, with the system keeping the valve open as long as needed. The setup replaces the conventional throttle valve, too, providing more dynamic and direct control over combustion and airflow. MultiAir technology can be adapted to diesels for enhanced NOx control.
https://www.allpar.com/mopar/multi-air.html
https://youtu.be/BK3CLMr8qwg
VTEC/Vanos/VVTI/MultiAir don't do this. They do timing and lift, which is different than duration. This is explained in the video.
I don't think you have taken the time to actually learn about MultiAir. It has complete control over timing, lift, and duration. To the point THERE IS NO THROTTLE.
The system uses electro-hydraulic valve actuators; a solenoid energized with each rotation of the camshaft regulates the amount of oil sent to the actuator, which controls the amount of lift from completely closed to completely open. Rather than having a limited number of positions between open and closed, there is infinite variation over the opening of the intake valves.
Unlike competing systems, MultiAir allows for each individual cylinder's valves to be adjusted independently, for faster responses.
Valve timing is also adjusted, with the system keeping the valve open as long as needed. The setup replaces the conventional throttle valve, too, providing more dynamic and direct control over combustion and airflow. MultiAir technology can be adapted to diesels for enhanced NOx control.
https://www.allpar.com/mopar/multi-air.html
https://youtu.be/BK3CLMr8qwg
Cost vs benefit . Think that is what you are saying ?
We had a 1989 Chevy Cavalier that would get 35 MPG winter ( no A/C ) highway on regular unleaded . We have a 2015 Chevy Sonic that does about the same .
Where is the progress , over the years & with the increase in technology ?
We had a 1989 Chevy Cavalier that would get 35 MPG winter ( no A/C ) highway on regular unleaded . We have a 2015 Chevy Sonic that does about the same .
Where is the progress , over the years & with the increase in technology ?
Originally Posted by WyrTwister
Cost vs benefit . Think that is what you are saying ?
We had a 1989 Chevy Cavalier that would get 35 MPG winter ( no A/C ) highway on regular unleaded . We have a 2015 Chevy Sonic that does about the same .
Where is the progress , over the years & with the increase in technology ?
More power and better MPG which results in a better driving experience in spite of increased weight resulting from meeting consumer demand for things such as larger size, more features, better safety.
Cost vs benefit . Think that is what you are saying ?
We had a 1989 Chevy Cavalier that would get 35 MPG winter ( no A/C ) highway on regular unleaded . We have a 2015 Chevy Sonic that does about the same .
Where is the progress , over the years & with the increase in technology ?
More power and better MPG which results in a better driving experience in spite of increased weight resulting from meeting consumer demand for things such as larger size, more features, better safety.
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Originally Posted by WyrTwister
Cost vs benefit . Think that is what you are saying ?
We had a 1989 Chevy Cavalier that would get 35 MPG winter ( no A/C ) highway on regular unleaded . We have a 2015 Chevy Sonic that does about the same .
Where is the progress , over the years & with the increase in technology ?
I make the same argument. It's clear that the better hybrid cars get the best MPG. But all the rest of the cars I rent seem to get about the same as they have always gotten, between 26 and 32mpg in real world use. Including the various Hyundai/Kia cars.
With a few clear exceptions: The new Camry does better than most at 35mpg, but it's NOISY due to weight cutting measures. Also the last generation Altima gets 36 highway MPG at high speeds. Both cars match the Fusion Hybrid real MPG with me at the helm....
At times I rent 2 or 3 cars per week, and often my shortest highway trip is 400 miles.
Cost vs benefit . Think that is what you are saying ?
We had a 1989 Chevy Cavalier that would get 35 MPG winter ( no A/C ) highway on regular unleaded . We have a 2015 Chevy Sonic that does about the same .
Where is the progress , over the years & with the increase in technology ?
I make the same argument. It's clear that the better hybrid cars get the best MPG. But all the rest of the cars I rent seem to get about the same as they have always gotten, between 26 and 32mpg in real world use. Including the various Hyundai/Kia cars.
With a few clear exceptions: The new Camry does better than most at 35mpg, but it's NOISY due to weight cutting measures. Also the last generation Altima gets 36 highway MPG at high speeds. Both cars match the Fusion Hybrid real MPG with me at the helm....
At times I rent 2 or 3 cars per week, and often my shortest highway trip is 400 miles.
4WD
$50 site donor 2024
We own a 2013 Cruze (can match MPG with those mentioned) and a 2014 Fusion Hybrid.
Two different drivers put 128k on the Chevy and 121k on the Ford so far in same area.
Different credit card numbers on same account. (mine).
Not one single month in years that the hybrid did not have lower fuel bills.
Two different drivers put 128k on the Chevy and 121k on the Ford so far in same area.
Different credit card numbers on same account. (mine).
Not one single month in years that the hybrid did not have lower fuel bills.
I can have no real world opinion on hybrids , never owned one . Only know what I read / hear .
Thought about a plug in hybrid like a Volt , but could not find a used one for the $$$ I was willing to part with . Plus , it was not as roomy , inside , as what I was looking for .
Something some people may not think about is the total dollar savings , as changed by changing MPG . Or , said another way , the % of dollar savings .
Compare , going from 20 MPG to 25 MPG . Then going from 30 MPG to 35 MPG . Also , factor in the cost of the vehicle and what that does to the cost of ownership , per year .
Also , the price of fuel plays a part . We had a Nissan Leaf , for a short time , until it was totaled . I tried to compare the cost of electricity vs. the cost of gasoline in the Chevy Sonic . Best I could tell , the electricity cost about 1/2 what the gas cost . But at ~ $ 2.00 per gallon for gas , the savings were not great .
Many things to consider when you are looking at things from the dollars and cents perspective . As opposed to just emotions .
Thought about a plug in hybrid like a Volt , but could not find a used one for the $$$ I was willing to part with . Plus , it was not as roomy , inside , as what I was looking for .
Something some people may not think about is the total dollar savings , as changed by changing MPG . Or , said another way , the % of dollar savings .
Compare , going from 20 MPG to 25 MPG . Then going from 30 MPG to 35 MPG . Also , factor in the cost of the vehicle and what that does to the cost of ownership , per year .
Also , the price of fuel plays a part . We had a Nissan Leaf , for a short time , until it was totaled . I tried to compare the cost of electricity vs. the cost of gasoline in the Chevy Sonic . Best I could tell , the electricity cost about 1/2 what the gas cost . But at ~ $ 2.00 per gallon for gas , the savings were not great .
Many things to consider when you are looking at things from the dollars and cents perspective . As opposed to just emotions .
Originally Posted by BMWTurboDzl
Originally Posted by WyrTwister
Cost vs benefit . Think that is what you are saying ?
We had a 1989 Chevy Cavalier that would get 35 MPG winter ( no A/C ) highway on regular unleaded . We have a 2015 Chevy Sonic that does about the same .
Where is the progress , over the years & with the increase in technology ?
More power and better MPG which results in a better driving experience in spite of increased weight resulting from meeting consumer demand for things such as larger size, more features, better safety.
MPG of today isn't better than what I get in my 1995 Ford Escort.
Originally Posted by WyrTwister
Cost vs benefit . Think that is what you are saying ?
We had a 1989 Chevy Cavalier that would get 35 MPG winter ( no A/C ) highway on regular unleaded . We have a 2015 Chevy Sonic that does about the same .
Where is the progress , over the years & with the increase in technology ?
More power and better MPG which results in a better driving experience in spite of increased weight resulting from meeting consumer demand for things such as larger size, more features, better safety.
MPG of today isn't better than what I get in my 1995 Ford Escort.
Originally Posted by zzyzzx
Originally Posted by BMWTurboDzl
Originally Posted by WyrTwister
Cost vs benefit . Think that is what you are saying ?
We had a 1989 Chevy Cavalier that would get 35 MPG winter ( no A/C ) highway on regular unleaded . We have a 2015 Chevy Sonic that does about the same .
Where is the progress , over the years & with the increase in technology ?
More power and better MPG which results in a better driving experience in spite of increased weight resulting from meeting consumer demand for things such as larger size, more features, better safety.
MPG of today isn't better than what I get in my 1995 Ford Escort.
Emissions have been improved
Safety features increasing weight have been improved
Originally Posted by BMWTurboDzl
Originally Posted by WyrTwister
Cost vs benefit . Think that is what you are saying ?
We had a 1989 Chevy Cavalier that would get 35 MPG winter ( no A/C ) highway on regular unleaded . We have a 2015 Chevy Sonic that does about the same .
Where is the progress , over the years & with the increase in technology ?
More power and better MPG which results in a better driving experience in spite of increased weight resulting from meeting consumer demand for things such as larger size, more features, better safety.
MPG of today isn't better than what I get in my 1995 Ford Escort.
Emissions have been improved
Safety features increasing weight have been improved
Originally Posted by zzyzzx
Originally Posted by BMWTurboDzl
Originally Posted by WyrTwister
Cost vs benefit . Think that is what you are saying ?
We had a 1989 Chevy Cavalier that would get 35 MPG winter ( no A/C ) highway on regular unleaded . We have a 2015 Chevy Sonic that does about the same .
Where is the progress , over the years & with the increase in technology ?
More power and better MPG which results in a better driving experience in spite of increased weight resulting from meeting consumer demand for things such as larger size, more features, better safety.
MPG of today isn't better than what I get in my 1995 Ford Escort.
The 2020 Mazda 3 weighs at least 20 percent more, is overall larger, has over twice the HP, offers better safety, and yet it has the same MPG's as the 1995 Ford Escort. On an inflation adjusted basis the Escort would run approx $16k vs 2020 Mazda 3 at $21k
Originally Posted by BMWTurboDzl
Originally Posted by WyrTwister
Cost vs benefit . Think that is what you are saying ?
We had a 1989 Chevy Cavalier that would get 35 MPG winter ( no A/C ) highway on regular unleaded . We have a 2015 Chevy Sonic that does about the same .
Where is the progress , over the years & with the increase in technology ?
More power and better MPG which results in a better driving experience in spite of increased weight resulting from meeting consumer demand for things such as larger size, more features, better safety.
MPG of today isn't better than what I get in my 1995 Ford Escort.
The 2020 Mazda 3 weighs at least 20 percent more, is overall larger, has over twice the HP, offers better safety, and yet it has the same MPG's as the 1995 Ford Escort. On an inflation adjusted basis the Escort would run approx $16k vs 2020 Mazda 3 at $21k
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