Cheers & Gears Weekend Edition - October 20, 2012

Agreed...pleasant Saturday morning read.

Regarding the C7...

It is safe to say that the C7 will have a more fuel efficient engine. Whether that will be a smaller displacement engine remains to be seen because a reduction in displacement does not necessarily equal an improvement in fuel economy. In fact, a reduction in displacement is a comparatively ineffective measure to reduce fuel consumption compared to an increase in the intake duration for instance, cylinder deactivation or simply the adoption of a taller axle ratio.

Regardless of what the displacement ends up being, it is safe to say the that there is absolutely no reason to believe that it will more likely be 5.5 liters vs some other (larger or smaller) displacement. The 5.5 liters mythology regarding the C7 arose from the fact that GM raced a 5.5 liter DI V8 in the C6-R with architectural roots in the Gen V engine. That displacement however has no relevance to production engines and is entirely dictated by class rules, in the same manner that Formula 1 rules requiring the cars to have 2.4 liter V8 engines have no bearing on the displacement of Ferrari production car V8s. DI was in fact subsequently deleted from the 5.5 liter C6-R engine, again compelled by changes in class rules. This also has no bearing on the incorporation of DI in the production Gen V engines.