KF CX-5 with Cylinder Deactivation coming to EU

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2019 CX-5 GT-R
KF CX-5 with Cylinder Deactivation appears only for Europe and only in 2.5, EU offers 3 engines 2.0,2.5,2.2D.
Engine is called Skyactiv-G1+ only with Auto Trans , in light cruising mode 2 cylinders are deactivated...save fuel.

Available only with automatic transmission
and all-wheel drive, the SKYACTIV-G1+ 2.5
petrol engine incorporates new technology
to enhance driving performance and lower
fuel consumption, including a cylinder deactivation
system that shuts down two of the
engines four cylinders under light loads,


80-cd_36392b45bc19ff4b8379933565f2a803716336db.jpg



SKYACTIV-G1+ 2.5 PETROL
ENGINE WITH CYLINDER
DEACTIVATION


With an aluminium block and other lightweight
components, a balance shaft that reduces
low frequency booming noise and a 13:1
compression ratio, the 2,488 cc SKYACTIVG1+
naturally-aspirated direct injection petrol
engine delivers excellent dynamic performance
and fuel economy, combined with a
notably quiet drive.
For installation in the all-new CX-5, the engine
benefits from a new cylinder deactivation
system for significant improvements in fuel
economy. It also adopts several combustion
enhancing measures, and new innovations to
further lower friction and noise, and increase
fuel efficiency.
The upgraded engine develops 194 PS at
6,000 rpm and 258 Nm of torque at 4,000
rpm. Equipped with automatic transmission
and i-ACTIV AWD all-wheel drive, it returns
combined cycle fuel economy figures of 7.1
l/100 km and generates CO2 emissions of
162 g/km.

CYLINDER DEACTIVATION SYSTEM
The SKYACTIV-G1+ 2.5-litre petrol engine
adopts a cylinder deactivation system that
shuts down two of the engines four cylinders
under light loads, such as when cruising at a
constant speed.
This is achieved via a switching mechanism
in the hydraulic lash adjusters of the first
and fourth cylinders. When running on all
four cylinders, these serve as the pivot point
for each rocker and the arms operate the
intake and exhaust valves. Applying hydraulic
pressure to the lash adjusters switches the
fulcrum to the valve side, stopping valve movement
to deactivate the two outer cylinders.
Because the firing interval is doubled when
running on two cylinders, engine vibration
is more likely, and the SKYACTIV-DRIVE
automatic transmission is equipped with a
centrifugal pendulum damper to compensate
for this.
Airflow intake volume, fuel injection rates
and ignition timing are all precisely controlled
to allow for the barely-perceptible switch
between two and four cylinders.

Cylinder deactivation is more effective at low
speeds, improving fuel economy by some
20% when driving at a constant 40 km/h, and
by about 5% at a constant 80 km/h.


ENHANCED COMBUSTION
The intake ports have been reshaped to generate
a stronger tumble flow during intake.
Reducing the height of the piston crowns and
optimising their shape also strengthens tumble
flow during compression and increases
the turbulent energy at ignition timing.
These factors cause faster flame spread when
the spark plug fires, and quicker combustion
completion, generating 2% more torque at
low- to mid-range rpm and a 3% improvement
in fuel economy at higher revs.
The tip of the multi-hole fuel injector has
been redesigned and fuel pressure increased
from 20 to 30 MPa, creating a faster and
more broadly dispersed spray, ensuring thorough
vaporisation and efficient, waste-free
combustion.
Three stage fuel injection is used when the
engine is cold and more likely to produce
particulates. This improves the vaporisation
and atomisation of the fuel, making it easier
to burn, reducing the formation of particulate
matter by some 80% and already conforming
to European particulate regulation coming
into effect in 2017.
Finally, a new coolant control valve reduces
the flow of coolant around the combustion
chamber walls to prevent heat from escaping
while the engine begins to warm up, shortening
engine warm up time whilst cutting
down the increase in fuel injection necessary
during cold starts.

REDUCED FRICTION

The sliding surface of the oil rings has been
given an asymmetrical shape, with a larger
outer radius at the top than at the bottom
edge, enhancing the oil smoothing process
and optimising the thickness of the film on
the cylinder wall to reduce friction.
The pistons now feature barrel-shaped skirts,
which optimise surface pressure under load.
In conjunction with the asymmetrical oil
rings, the new skirts significantly reduce
mechanical resistance, contributing to better
fuel economy.



stay tuned guys, working on getting you more info, sources, etc.


Thoughts?
 
:
'18 Mazda CX-5 Akera KG i-Activ AWD 2.5L In Sonic Silver
Better fuel economy is nice but 143KW (192bhp) and 258NM (191ft/lb) is not much of an improvement over the current engine.

Our current 2.5L has combined fuel of 7.5L/100km. This one is 7.1L/100km.

When is this engine supposed to be released into the CX-5?
 
:
2019 CX-5 GT-R
xeler8ing: I wasn't sure how much of a difference that was for you guys and I'm way too lazy to try and convert that to US.
I'm working on getting those details from my source at Mazda.


p.s. Awesome avatar.
 
:
'18 Mazda CX-5 Akera KG i-Activ AWD 2.5L In Sonic Silver
xeler8ing: I wasn't sure how much of a difference that was for you guys and I'm way too lazy to try and convert that to US.
I'm working on getting those details from my source at Mazda.


p.s. Awesome avatar.

Did it for you :)

And thanks! :D
 

yugrus

Contributor
:
CX-5 GT
Fixed cylinder deactivation = very bad idea, ask GM.

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:
'18 Mazda CX-5 Akera KG i-Activ AWD 2.5L In Sonic Silver
Fixed cylinder deactivation = very bad idea, ask GM.

Sent from my VIVO XL using Tapatalk

But if they have mastered it.....

Unless the this engine changes the way the 2.5L performs, for a 0.4L decrease in fuel consumption seems not worth waiting for it to come online (if it is indeed released to Australia/Japan/USA)
 
:
CX-5 II 2.5L Skycruise AWD AT 192hp
Anybody knows of a video showing how this 2.5 L with cylinder deactivation technically works?
 

yrwei52

2016 Mazda CX-5 GT AWD w/Tech Pkg
Contributor
:
Plano, Texas, USA
Fixed cylinder deactivation = very bad idea, ask GM.
Exactly! You close the valves but your piston is still moving up and down. The "deactivated" cylinders create not only air compression but also decompression which require more energy. It won't be as efficient as most people thought like a true 2-cylinder engine. I can understand Honda uses Variable Cylinder Management (VCM) system on its V6 to save a little more fuel, but I don't think it has significant benefit on an already fuel efficient I4. Besides Honda's VCM is the only engine in the US using cylinder deactivation system and nobody else follows them. GM has given it up long time ago. And Honda's VCM has been experiencing excessive oil usage、fouled spark plugs、and misfire. A class-action lawsuit against Honda for these issues caused by VCM was filed a while ago. And this "cylinder deactivation is more effective at low speeds, improving fuel economy by some 20% when driving at a constant 40 km/h, and by about 5% at a constant 80 km/h." Who's driving at constant 25 mph to get the best fuel efficiency with only two crippled cylinders? To save 0.4L/100km or 1.7 mpg? Not worth all the efforts and risks with a proven problematic technology!
 

yugrus

Contributor
:
CX-5 GT
Seriously guys. Unless valves are 100% electric-driven, cylinder de-activation is only good for 3-4yr lease. It will not save you any money, but you'd be good feeling you're saving the planet. Otherwise this is bad. People pay some good money to get rid of it in GM trucks. I did, and I don't regret it. Oil-controlled variable-displacement lifter- enabler idea proved total disaster in GM V8 engines. They have followed up with this in the new generation trucks, and the educated owners disable that as soon as they can. It does nothing for the real world fuel economy, but is proven to cause all kinds of issues in de-activateable cylinders. The MPG effect will be even less noticeable in the engine half the size, with ALL negative effects present. Very wrong move. SAD...

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yrwei52

2016 Mazda CX-5 GT AWD w/Tech Pkg
Contributor
:
Plano, Texas, USA
Maybe they have mastered it. Time will tell
Sometimes you can never overcome the inherent major flaw no matter how hard you're trying - such as oil consumption on rotary engine ⋯
 
:
'18 Mazda CX-5 Akera KG i-Activ AWD 2.5L In Sonic Silver
Sometimes you can never overcome the inherent major flaw no matter how hard you're trying - such as oil consumption on rotary engine ⋯

True. I will say the over here we had Chevy's V8 with cylinder deactivation in our Holden Commodore (called Active Fuel Management) and generally seemed to be fine.
 

NelsonLewis

Banned
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16.5 CX-5 GT AWD w/Tech BRMica
Maybe they have mastered it. Time will tell

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Mastered something that isn't needed to begin with isn't much to master IMO, but you're right time will tell, and the same goes with when it comes time to buy another new car, this is looking more and more like my first and only Mazda...
 
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'18 Mazda CX-5 Akera KG i-Activ AWD 2.5L In Sonic Silver
Mastered something that isn't needed to begin with isn't much to master IMO, but you're right time will tell, and the same goes with when it comes time to buy another new car, this is looking more and more like my first and only Mazda...
I'd say this engine is a stop gap until their HCCI engines come on line during the later half of this decade.


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NelsonLewis

Banned
:
16.5 CX-5 GT AWD w/Tech BRMica
I'd say this engine is a stop gap until their HCCI engines come on line during the later half of this decade.


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You may or probably are right, but I'm not really interested in those either. Granted, I can see why they are interested in mastering that route, but there path seems more disastrous than advantageous to me. I hope I'm wrong, but it'll drive me away, maybe it will bring in butt loads of others...
 
:
'18 Mazda CX-5 Akera KG i-Activ AWD 2.5L In Sonic Silver
You may or probably are right, but I'm not really interested in those either. Granted, I can see why they are interested in mastering that route, but there path seems more disastrous than advantageous to me. I hope I'm wrong, but it'll drive me away, maybe it will bring in butt loads of others...
I'd say they will loose some customers but also gain a fair few others

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