Dynamic Skip Fire: GM hopes to use cylinder management tech to increase efficiency by 15%

By Andrew Hard January 6, 2015

Cylinder deactivation, the act of shutting off predetermined arrangements of pistons to save fuel, is nothing new.

Also called variable displacement, the engine management system has existed in concept form for decades, and today, you’ll find variants of it in newer cars from Honda, Mercedes-Benz, Audi, and General Motors.

With the help of Silicon Valley startup Tula Technology, GM is looking to take the fuel savings one step further by employing something called Dynamic Skip Fire (DSF).

Instead of shutting off entire cylinder banks, DSF analyzes each piston individually, determining whether to ignite or bypass it based on the driver’s throttle input and torque demands. According to the automaker, the system has shown fuel savings of up to 15 percent when compared to an engine without cylinder deactivation.

“This technology holds the potential to improve fuel economy on select GM vehicles without degrading power capability when it’s required,” said GM Chief Technical Officer Jon Lauckner. “This joint effort combines software expertise from Silicon Valley with powertrain expertise from General Motors.”

DSF is primarily a software-based approach. However, in order for it to work, the engine must already have cylinder deactivation hardware installed. There are always concerns about vibration when altering the firing order, but GM claims the technology avoids excessive reverberation while providing the required engine torque.

The program is still in the testing stages, but with fuel efficiency standards rising, Tula Technology and GM seem committed to making DSF production-ready.

“We’ve worked closely with GM during this exciting stage of DSF development, and they’ve provided essential financial support while allowing us to run our business with full autonomy,” said R. Scott Bailey, CEO of Tula Technology. “Our goal is the same as GM; we both innovate to make the lives of people better.”

Former Digital Trends Contributor

Andrew first started writing in middle school and hasn't put the pen down since. Whether it's technology, music, sports, or…

Cars

Best electric car charger deals: $100 off home charging stations

The handle of the Grizzl-E EV charger plugged into a vehicle.

A few years ago, electric vehicles were pretty rare or cost a fortune, but with more and more of the larger car brands getting into the game, there are a lot of excellent and even budget-friendly choices nowadays. That said, the electrical network for charging your cars might not be that widespread, so instead you'll have to rely on charging your car at home. Luckily, there are a lot of excellent car chargers at a discount, so if you've just bought an EV or want to upgrade your current charging solution, be sure to check out our favorite deals below.
Shockflo EV charger — $205, was $220

This EV charger by Shockflo is a Level 2 EV charger, which offers six times faster charging than a standard charger. It delivers 24 miles with just one hour of charging, and it can act as a mobile charger you can throw in the trunk or be mounted to a wall. It has an LCD display with useful information like charging rate, voltage, and charging time, as well as LED indicator lights that lets you know charging progress and errors.

Cars

Mercedes-Benz EQG: range, price, release date, and more

Concept image of the larger electric G-Wagon

The G-Class is going electric. We already knew that Mercedes-Benz was working on an electric, small-size G-Wagon, but it looks like the company is also working on a larger G-Class SUV, in the form of the EQG. In fact, Mercedes has gone as far as to show off a concept version of the off-roader.

While there's much we don't know about what will become the production model of the EQG, Mercedes has also shared a lot about it. Curious about whether the Mercedes-Benz EQG could be the EV for you? Here's everything we know so far.
Design
Fear not -- the EQG will retain many of the design aspects of the G-Class that you already know and love but with a modern face-lift. The EQG will keep the boxy design that gives the G-Class a classic look but with some additional modern styling, at least if the concept version is anything to go by.

Cars

Rivian R2 vs. Kia EV9: battle of affordable electric SUVs

Kia EV9 GT-Line Three Quarters

The long-awaited Rivian R2 has finally been announced, and it's an excellent option for those who want an electric SUV that doesn't completely break the bank. Sure, the R2 isn't cheap -- but it's a whole lot cheaper than most other EVs out there, especially when it comes to SUVs. But Rivian isn't the only company trying to tackle the problem of the budget electric SUV. The Kia EV9 is finally available, and it too offers a modern design and a range of helpful features.

Given the fact that the Rivian R2 and Kia EV9 are two electric SUVs in a similar price range, you might be wondering which is better for your needs. That's why we put the Rivian R2 and the Kia EV9 head-to-head.
Design
Both the Rivian R2 and the Kia EV9 are actual SUVs -- not crossovers pretending to be SUVs, like plenty of other EVs out there. The two vehicles offer big, boxy designs and plenty of interior space, making them excellent options for families or those who need that extra storage.