I just moved the thread...It's become much less "Camaro-Oriented" than I think was intended. No help from me, I'm sorry to say.
Scotsman, you're right. I don't keep up with those brands
at all. So Honda has beat GM to the punch...aw well - at least we know it's possible.
It's called VCM on the Honda engine. Uses little 'pins' I guess that disconnect the rockers from the cam followers. It can switch from 6 to 4 to 3 cylinders depending on load. And on 3 cylinders, one full bank of the engine is shut down...