Fuel economy.
The EPA recently changed their fuel economy calculations to take into account "real world driving" rather than laboratory figures. Here is a link to the epa website for further reading.
http://www.epa.gov/fueleconomy/420f06009.htm
The northstar is a gem of engineering. The ohc 32valve drivetrain is brilliant, and much more efficient than a pushrod 16valve motor could ever fantasize about. Honestly, it's less complicated mechanically. MUCH fewer moving parts, and the layout of which makes a LOT more sense. The fuel/spark control is much more sophisticated (you could pronounce that complicated, but i like sophisticated:biggrin
enabling the fuel delivery and timing to be MUCH more precise. Again, increasing economy.
Look for a How It Works in the near future (going to continue ground up with suspension next, i'll do engines after, and cover the northstar, since they are starting to put them in rear drive cars, and I believe even a buick, and someone might just feel like putting one in a b body, or derivative) about the difference. I'll go into the differences and how the advances in technology are better for the cars and industry in moderate detail, it'll make sense then hopefully.
