Bob Lutz did an interview, for the GM blogs saying something along the lines of Diesels and gas-engines becoming more and more alike, (in terms of emmisions.) Which is why GM hasn't undertaken a widespread use of diesel powertrains. It'd be cheaper(maybe not), and simpler just to continue advancing gasoline engines.
Now, he's not God, and I know that, but he's close
I guess what I'm saying is that pushrods have had their day...they'll be around for some time to come, but very generally speaking, the age of the pushrod is over. and I'm confident (knowing what GM could do with pushrods) that we're in for a wild ride with these Overhead Cammers!
