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General Motors created a new engine that has many people talking about it. With its impressive specs, it’s still a bit confusing as to what they actually meant it for.

The new four-cylinder engine promises to revolutionize performance. Jason, from Engineering Explained, goes over why this engine is so impressive and why it has us scratching our heads. 

Why has this new GM engine garnered so much attention?

First, GM touts the new motor as a truck engine. It’s built, designed, and created for trucks. There’s nothing inherently wrong with that, but what’s drawing attention is the fact that they used this engine in two different vehicles. One is a Chevy Silverado, which, of course, is a truck. 

But, it’s the other vehicle, they dropped the motor in that has people talking. What is it? Well, it’s the Cadillac CT4-V. Did Cadillac build a new truck? Nope, it’s just their compact luxury sedan. You read that right, it’s a car, not a truck. So, why does a car have, what essentially is supposed to be, a truck motor?

The second reason for all the attention is that it’s not just any four-cylinder motor. It’s, perhaps, the largest four-cylinder engine placed in a car. This innovative motor could turn the heads of many automotive enthusiasts. 

Overview of the new GM engine

GM Authority explains that this is GM’s 2.7-liter Inline four L3B Turbo engine. Designed to achieve stronger lower end torque, the L3B uses a long-piston technology to offer better combustion, which improves the compression ratio. 

To combat the increased friction that you would typically see with longer pistons, GM designed an offset crankshaft to allow the connecting rods to operate in a more upright position. 

What’s even more impressive about this motor is the dual volute system it uses. Similar to the twin-scroll turbocharger, this system strives to maintain better efficiency and a lower-end torque.

 It’s able to do that by separating the two exhaust pulses, one going through one volute and the other going through the second one to avoid them interfering with each other. 

Another feature of this motor is the 3-position camshaft it has. This technology allows for varied performance. One position profile is a high lift for the most power. Then there’s a medium profile for efficiency and the last one allows for a two-cylinder operation. 

It also uses the Active Fuel Management system, which conserves fuel by controlling the cylinders. This system works by shutting down two of the four cylinders to allow for less fuel being used up in light load conditions. 

How well does it perform?


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It’s interesting to note that despite the engine being installed in the Silverado and the Cadillac CT4-V, performance varies a bit. The Silverado’s motor offers 310 hp and 350 lb-ft of torque.  

When it comes to gas mileage, the pickup gets 23 mpg on the highway. But a V8 variant motor, as Jason from the Engineering Explained video, points out, offers 24 mpg on the highway. This makes you wonder whether their V8 engine can outperform the inline-four. 

When you see the motor working in the Cadillac CT4-V, you’ll find the engine gets you 325 hp with 380 lb-ft of torque, using premium fuel in its tank. For fuel economy ratings, you’ll notice the Cadillac gets 29 highway miles per gallon. 

The new engine, obviously, isn’t just for trucks, despite all the marketing hype GM put out touting the benefits it brings pickups. We find the L3B motor, in its prime state, only in the Cadillac sedan. Sure, the Silverado has it, but the tweaks they did for its performance, doesn’t match what it does for the CT4-V. If all goes well, we may find it standard in SUVs and all other vehicles too.