Cylinder deactivation module?
Discussion
ReverendCounter said:
I'm trying to find some info about an installer of modules which temporarily shut down some cylinders under low load, but I can only find ones aimed at the US pick up truck market.
It's just an enquiry based around interest rather than needing one installed, but any pointers please?
To what end ?It's just an enquiry based around interest rather than needing one installed, but any pointers please?
When OEM do it....it is not how you are thinking in just shutting off fuel or spark to a cylinder. It is a fully integrated setup also involving mechanical parts.
I just recall some vid or other a few years ago, someone had an installation carried out that was described as being simple and easy to remove, which shut two or four cylinders down of a v8 when it wasn't under any significant load, but there doesn't seem to be anything on the UK market.
Maybe as fuel prices get higher there could be more interest.
Maybe as fuel prices get higher there could be more interest.
ReverendCounter said:
I just recall some vid or other a few years ago, someone had an installation carried out that was described as being simple and easy to remove, which shut two or four cylinders down of a v8 when it wasn't under any significant load, but there doesn't seem to be anything on the UK market.
Maybe as fuel prices get higher there could be more interest.
No, because without shutting down airflow through the cylinders, it would play havoc with any closed loop fueling corrections, and in turn any emissions related devices.Maybe as fuel prices get higher there could be more interest.
As said, it is not a simple process a DIY'er can do simply by shutting off fuel or spark to some cylinders.
https://www.rangetechnology.com/blog/post/what_is_...
VW Group do it with their 1.4 ; 1.5 TSI engines
https://www.greencarcongress.com/2011/09/zas-20110...
https://www.greencarcongress.com/2011/09/zas-20110...
I don't recall which one, but one of the outboard boat engine manufacturers have/used to have a similar device on some of their engines which drops two cylinders at idle/low revs.
Has caused confusion with people asking on websites thinking that their engine has a fault.
Perhaps the UK firm stopped doing it/went out of business as there was little call for it?
Has caused confusion with people asking on websites thinking that their engine has a fault.
Perhaps the UK firm stopped doing it/went out of business as there was little call for it?
paintman said:
Perhaps the UK firm stopped doing it/went out of business as there was little call for it?
Seems like it. My thoughts are, if fuel costs continue to spiral then maybe at some point it might be a more attractive proposition to have something installed that could do the job properly if it was possible - or maybe the UK outfit came up against issues and decided to close down, given the points raised re: the complexity.Doing such things will make almost negligible difference to fuel used.
If you want to use less fuel...go easier with the right foot. It is 100% tried and tested, and basically free.
Some car makers choose to do such things to reduce emissions....rarely does it ever actually decrease fuel consumption in the real world.
Any claims it does...are about as honest as their overall mpg claims. Complete and utter lies.
If you want to use less fuel...go easier with the right foot. It is 100% tried and tested, and basically free.
Some car makers choose to do such things to reduce emissions....rarely does it ever actually decrease fuel consumption in the real world.
Any claims it does...are about as honest as their overall mpg claims. Complete and utter lies.
stevieturbo said:
Doing such things will make almost negligible difference to fuel used.
If you want to use less fuel...go easier with the right foot. It is 100% tried and tested, and basically free.
Some car makers choose to do such things to reduce emissions....rarely does it ever actually decrease fuel consumption in the real world.
Any claims it does...are about as honest as their overall mpg claims. Complete and utter lies.
Interesting, on face value it would seem to be a decent proposition. Thanks.If you want to use less fuel...go easier with the right foot. It is 100% tried and tested, and basically free.
Some car makers choose to do such things to reduce emissions....rarely does it ever actually decrease fuel consumption in the real world.
Any claims it does...are about as honest as their overall mpg claims. Complete and utter lies.
ReverendCounter said:
Interesting, on face value it would seem to be a decent proposition. Thanks.
Where do you imagine the saving coming from? Unless you're cutting off the air flow somehow, the pumping and friction losses are essentially unchanged between a lightly loaded cylinder and a deactivated one.Cutting the fuel injection on its own takes you nowhere worthwhile. You need mechanical interventions as well,
- to lift the relevant valves and reduce pumping losses,
- to switch the exhaust system to a different route for exhaust scavenging.
OE cylinder de-act round-robins the shut down cylinders to maintain even temperatures and to prevent piston ring polishing (rings need firing loads to work!) and excessive oil consumption. They also de-activate valves to avoid excessive pumping losses and to prevent a lean exhaust AFR that messes with fuel control and destroys catalyst efficiency.
if you really want to "turn off cylinders" just cut the power to some of the injectors, but the engine will wear out, burn oil and misfire like a good un......
if you really want to "turn off cylinders" just cut the power to some of the injectors, but the engine will wear out, burn oil and misfire like a good un......
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