Originally Posted by JAJ
I'd have to disagree with all of you and say it was the original 1960's inline four designed by Alex Von Falkenhausen. They built that engine and variants of it for twenty years and it powered the cars that turned BMW from an unknown into the successful giant it is today.
It was a very simple and strong design - I've rebuilt a couple and they're remarkably simple to assemble. How strong? Well it's the same block that became the turbo F1 engine.
The modern BMW engines are superb pieces of engineering, but not one of has stayed in production for 20 years. Yes, that's because of changing standards and so on, but still, the old four-banger made BMW what it is today. It wins!
With you I agree, almost all of us have had the legendary M10 motor in one of our BM's and I have had it in three: 2000. 2002 and 318I. Legend has it the blocks were thrown away and urinated on for two years before final machining into what became the F1 engines (helped the stress relief of the blocks).........go figure!
A bit later I see a mention to aircraft engines, although not succesful, I believe the BMW 109-003 turbo jet to be an advance for basic aircraft engines we see on all Boeings, airbusses ect today even though the Junkers 109-004 did better it, it used the 003 principles for blade retention and materials.