[epbrown]

Hmm - are we talking technical innovation, durability, or performance here? All three?

I like the RR inline 6, the BMW inline 4, 944 3.0L I-4, and the Chevy 350 V8.

The I-6 used in the post-war Rolls-Royces (1945-1962) are perfection for the cars - smooth, quiet, durable, efficient, and good performance. To me, the post-war years (before the Silver Shadow) are the pinnacle of the marque and thus the pinnacle of car-making in general (hey, it was the "best car in the world" after all.) I think those cars could be driven for a lifetime, and you'd never want another.

The BMW 4-cylinder M10s represent, to me, the pinnacle of small engines. I include the 944 3-liter not because I'm overly fond of it, but because of the genius it represents in out-doing BMW's I-4. Impressive.

The 350 for it's sheer versatility - tuned properly you get a monster performer, left alone you get a solid, all-around engine good for most anything that will run forever if cared for properly, and it is so ubiquitous you could likely rebuild one from parts found at the average Shell station. The automotive equivalent of AA batteries. Of the criteria I named above, I'd give it the prize for meeting them all.

Emanuel