It will most likely be quite some time before mass adaptation of alternative-fuel, or electric vehicles, takes hold. Until then, it’s a race against the clock to develop the next big thing in powertrain technology to make vehicles more efficient, and even more frugal, especially larger SUVs and trucks.
General Motors announced it had invested in Silicon Valley software startup, Tula Technologies, but it was not known what GM had in store with the investment. It’s become clear after Delphi and GM showed off what could be the next greatest innovation: Dynamic Skip Fire, or DSF.
How it works is DSF is applied to each individual cylinder, and it continuously varies which cylinders must be firing, as it works in sync with the engine’s throttle system. In normal engines, the flap in the throttle body is almost always in a closed position but, with DSF, the flap is nearly always open to control the engine’s power by varying the number of cylinders needed.
The cylinders are shut off by stopping the flow of oil with special valve lifters on each cylinder.
“The more power you need out of your engine, the more torque, the harder you press down on the accelerator pedal, the greater percentage of your cylinders will fire. This is software-enabled variable displacement,” Tula CEO, Scott Bailey, told Automotive News.
Tula says a V8-powered SUV typically only requires 30 hp to cruise on a highway to hold its speed and, with DSF, six cylinders shut down to provide a monumental 21-percent increase in fuel economy, as tested in the real world on a GMC Yukon Denali.
Tula says the technology can be applied to any engine application greater than four-cylinders. During the technology’s presentation, the company said the first GM vehicles with DSF could arrive by the year 2020.
Could your Camaro or Corvette suddenly garner nearly 30 mpg? Quite possibly.
Comments
“Could your Camaro or Corvette suddenly garner nearly 30 mpg?”
The Corvette’s already can. I know a guy with a C7 w/ the Z51 package who regularly gets 31 mpg @ 75mph cruising. They do this with through less wind resistance and a low top gear cruising RPM in addition to the cylinder deactivation in the current LT1 engines.
With this new software controlled displacement, I can see that rising to 35mpg – maybe more. Who would have thought it possible 15 years ago?
People already have enough issues with AFM in GM trucks that there are specific tunes and OBD dongles that deactivate it. This should be good.
Say I’ve just purchased a brand new Corvette Stingray, yeah I don’t want it to get Hummer mileage, but I’ve purchased a 460 hp V8 performance car. I fully understand I’m not gonna be beating hybrids when it comes to mileage. This seems pointless for that. Now on the trucks and SUVs, sure.
Well here is the deal here.
GM is one of the few who are really working to prolong the life of the V8.
Ford has abandon it for the most part and it will fade away there at some point. Chrysler is said to be dropping it in 2019. While it sounds like a false story the truth is FCA really does not have the money to do as GM is doing with the V8.
While the V8 is getting good MPG now it will still not be enough moving ahead. Also while people do not expect big MPG the Corvette and Camaro are not exempt form meeting higher levels from the EPA and from GM. GM has made it clear they will not leave any product out.
I have a scan meter on my car that measure many parameters and one is HP. As the story points out it takes little to push a car down the road at speed. If they can kill cylinders at the right time and speed it can be done on 2 cylinders. The key will be refinement. You can not have much hesitation for them to kick in if you need power. Right now our new Chevy truck has a slight lag in kick down that I feel is part of the cylinder drop. I expect this to improve with this new system.
Ford has not abandoned v8s.
The 5.0 Coyote is only 4 years old, and it gets good milage without cylinder deactivation.
Plus the 5.2 Voodoo is brand new.
And the 6.2 is only 5 years old, we have it in our work truck it’s awesome.
Now there’s talks about (Not so) ecoboost 5.0s and D.I.
You should comment on GM products only, your far to biased to give out correct information about any other manufacturer.
Ken you really need to look at what is going on.
The only V8 Ford car is the Mustang.
The next Ford $400, 000 Super Car is not going to be a V8 but a TT V6. Then look to the trucks and the top line performance model the Raptor is going from a V8 also to the TT V6.
Now yes they still offer it in the trucks and Mustang now but I believe they have shown the direction they are going and the engine will be found in less and less models.
Ken this is a case where the V8 is going to be limited or eliminated in most brands outside some high end cars.
Before your critic others comments you had better get the correct information on where the market is going.
Before long the odds are the only Ford to offer a V8 will be a heavy Ford truck as the half ton will not be able to support it by 2025 with MPG. The Mustang too may either not have one or if they do it will be in a high end Shelby. Rumors are the next Shelby is going TT V6 too.
You really had better look around but The V8 is nearly gone from Ford now. Ford will carry the while longer but unless they make some other radical moves I think in the car line it will be gone in the next ten years. It may only be found in 3/4 and 1 ton trucks because of the lower regulations. It also will be much more expensive to limit sales.
GM as of now is the only American Brand that really is showing signs of trying to protect the V8 in some fashion by technology to expand the MPG by some crazy engineering. Even here it will see fewer vehicles it is offered in.
Ken there is no bias here just the observations of what is going on in the market. All three American companies will limit or eliminate the V8 due to the coming regulations. If these engines are offered it will only be in the most expensive models to limit their sales. Ford Scares me as they really are showing little love for the V8. Things could always change as Lincoln almost died too from the lack of love inside Ford but regulations are not going to get better. Ford has already shown they are willing to put all their chips on the 6 blue.
I make my living in the performance industry and the last thing I want to see is the lack of V8 engines from any MFG. I live well off of sales for Mustang V8 parts. I may not want to rush out to buy one but I want the car to do well in the market as if it does well so do I.
Scott, I think the lag you’re feeling in your new truck could also be a result of programming with the drive by wire and transmission calibration. I’m assuming when you say kick down, that you mean a downshift when you put your foot in it. Recently going from an ’01 Grand Prix with a throttle cable and a 4speed auto to a ’15 Sonic RS with electronic throttle and 6speed auto, I’m having to adapt to the different throttle response and transmission lag.
I’ve heard similar complaints about the delayed downshifting on the shared 6 speed transmissions in Ford and GM products.
It could be or even a combination of several things.
It is not a problem just a personal anoyance.
I have had this in two trucks with cylinder drop.
The lag to kick down a gear is much longer than my turbo lag on my other car.
It would be nice if everyone wasn’t so hung up on the number of cylinders. If anything, the work GM is doing with the V-8 can be applied to I-4’s and V-6’s to boost economy across the board. With this software controlled displacement by dynamic skip fire (DSF), the number of cylinders becomes irrelevant as this properly puts the focus on how much air is being pumped (and by extension, how much fuel is consumed). This technology is an alternative to forced induction methodologies.
With forced induction, a smaller engine pumps more air/fuel than the equal displacement N/A engine to make more power when it needs it. Under full load and a moderate 15psig of boost, a turbo 2.0 will have similar economy as a 4.0 N/A engine.
With the DSF, a larger engine can pump less air/fuel to behave like a smaller engine. This allows the throttle plate(s) to be more open to improve volumetric efficiency under lighter loads. A turbo motor can’t do that.
I can see additional incremental improvements on the horizon to improve V-8’s even more. Imagine combining this technology with solenoid operated valves. As processer speeds and solenoids advance, this will become a reality. You can reduce parasitic drag by removing the camshaft, lifters, rockers, timing chain, etc. – Less moving parts. You can independently control valve overlap for better low end torque and high end power.
It will get to the point where the amount of cylinders becomes immaterial.