Ok, some info on the new GM mild-hybrids:
Available in the 2007 Saturn VUE, Saturn Aura, Chevrolet Malibu
It's known as a BAS or Belt Alternator Starter system. The electric motor/alternator drives the engine through a very large belt. It uses a 36v NiMH battery pack, and can provide mild boost to the engine for acceleration.
What I found most interesting is where the 12% claimed benefit in fuel economy comes from:
3% to LRR tires
4% to Auto Stop (Hybrid Function)
3.5% to new Defuel Cutoff (ECM Programming)
1% to Regen braking (Hybrid Function)
4.5% to Engine/Trans/Driveline optimizations (some of this is also in ECM programming)
0.5% to Aerodynamic modifications
That means that 5% of the fuel economy comes from the actual Hybrid strategy. The question I have: Why doesn't GM incorporate the other 7% benefits to the conventional Malibu/Aura/VUE?
I'll provide more specifics on the details of the modifications as I have time