In yesterday's Wall Street Journal, writer Jeff Bennett looks at the leading candidates to replace Dan Akerson as CEO when he retires. Unfortunately, between the the writer and his editors, there is a fundamental misunderstanding of how vehicles are actually engineered and built.

In his section on product development chief Mary Barra, he appears to have paraphrased her words without actually knowing what they meant and in the process completely mangled them. 

Until recently, many GM vehicles were designed to accommodate the biggest engine available in the model line, even if only 20% of customers ordered it. The result, Ms. Barra says, is that many GM cars and trucks carried "scar mass," or extra weight that undercut fuel economy. Vehicles were loaded with the same-sized engine block no matter how many cylinders were needed. For a four-cylinder, four holes were drilled and the rest was just unused weight.

A journalism degree is far from adequate qualification to practice real journalism. The journalist needs to actually understand the topic they are writing about. They also need to be humble enough to acknowledge when they don't and ask questions until they do.

Bennett is by no means unique in doing this, but this is a great example. 

FWIW, Vehicles are engineered to accommodate the largest engine they need which can lead to structures and other components like brakes that are over-engineered for the highest volume variants. A four cylinder engine is not made by only drilling four holes in a V8 block. Different engines have unique blocks. The so-called "scar mass" that Barra referred to is a structure that can support the weight of V8 when 80% of the vehicles built carry a four or six cylinder.