Never heard of Ford doing it, nut GM and Dodge have done it. The new Hemi from Dodge shuts down cylinders through hydraulics in the lifters.
When looking at hybrids, you have to do a cost benefit analysis. Right now, the present new hybrids give up their mileage gains in purchase price and battery replacement. The benfit to an individual is purely feeling good.
When looking at hybrids, you have to do a cost benefit analysis. Right now, the present new hybrids give up their mileage gains in purchase price and battery replacement. The benfit to an individual is purely feeling good.
Yep, I've read about "displacement on demand" for the last few years, but it hasn't been isolated to new car manufactureres. With the development of stand-alone engine management systems (like TEC II), I've heard of folks like Trepanier doing the same sort of thing on some of his projects with tradition pushrod motors. It seems simple enough in theory... program an algorithm for the engine management computer that takes certain input data (like vacuum readings, O2 sensor readings, maybe throttle position, etc.) and then doesn't fire the injectors or plugs for whichever cylinders. I just wonder how you decide which cylinders to drop... maybe it has to do with balancing the stress on the rotating assmebly?
My point is that with some good research and some well spent dollars, I'm guessing you could probably achieve something comparable to "displacement on demand" without spending wads of cash on a late model conversion.
Hope this helps.
My point is that with some good research and some well spent dollars, I'm guessing you could probably achieve something comparable to "displacement on demand" without spending wads of cash on a late model conversion.
Hope this helps.
ford in fact along with eaton was a pioneer in the displacement on demand system. they started working on a system in the late 70's that would shut off cylinders to reduce both emissions and fuel consumption. while ford has continued developement over the years, they have not made a system for public consumption due to cost, reliability, and other concerns.
Most of these systems do help a little with mileage, but not alot.
There is so much more to fuel efficiency than just displacement. Reciprocating mass for example will stay the same.
It's a step in the right direction, but it will never give you the fuel economy of a 4cyln while running on only 4 cylinders.
It's been used/tried in 1 sort or another for many years. In fact, your EGR system is a primative version of displacement on demand. Exhaust gasses enter the cylinder effectively "taking up space" and lowering your would-be displacement.
There is so much more to fuel efficiency than just displacement. Reciprocating mass for example will stay the same.
It's a step in the right direction, but it will never give you the fuel economy of a 4cyln while running on only 4 cylinders.
It's been used/tried in 1 sort or another for many years. In fact, your EGR system is a primative version of displacement on demand. Exhaust gasses enter the cylinder effectively "taking up space" and lowering your would-be displacement.