GM Speaks Directly About Next-Gen Small-Block 
Direct-Injection Fuel System Picture
A new direct-injection fuel system will help GM's Gen-V small-block engine deliver greater fuel efficiency compared with the current generation.
Just the Facts:
- General Motors said its next-generation small-block engines will feature direct fuel injection.
- GM says production of the Gen V small-blocks begins "in the near future."
- The Gen V family will be an all-new architecture, GM promises, but will retain the small-block family's hallowed 4.4-inch spacing between bore centers.
WIXOM, Michigan — At an event today to commemorate the construction of its 100-millionth small-block engine, General Motors announced that the next generation of its nearly 60-year-old engine family will feature direct-injection fueling. The company's skimpy-on-details release said direct injection will combine with a higher compression ratio and "other technologies" to enhance efficiency.
One GM engineering executive told Inside Line that although almost 80 percent of all engines manufactured in the world currently are four-cylinders, GM has no intention of abandoning the V8, even in the face of a 35.5-mpg Corporate Average Fuel Economy requirement in 2017. He said the Gen V small-blocks are vital to GM's standing in the U.S.'s performance-car and pickup segments.
The industry is moving toward widespread fitment of direct injection, which generally improves fuel economy while also boosting low-rpm torque, so GM's announcement is no surprise — direct injection had for some time been rumored to be a central feature of the new-generation small-block engines.
What's more intriguing is what GM didn't say today: There are rumors a new "base" displacement for the Gen V small-block V8 will be 5.5 liters and there might be something special going on with the valvetrain.
It's long been speculated that GM might have an engineering surprise up its sleeve to improve the relatively narrow degree of variable valve timing available from the small-block's single-cam, pushrod valvetrain — one feature that many argue holds back the engine's development potential.
Inside Line says: Direct injection surely will be an improvement for GM's time-honored small-block engine design. We'll have to wait for what other surprises are coming for its fifth-generation architecture
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