New York Times reports that GENERAL MOTORS is going to spend $225 million on developing a 3-cylinder motor. Maybe ELIO can sell some to them and cash in on the BIG BUCKS !
Ford will soon be putting a 1.0l 3 cylinder Ecoboost(123hp, 148ft-lb) in the Fiesta. Mini will be putting a 1.5l 3 cylinder in the Cooper. Fiat has a 0.9l 2 cylinder CNG engine in the 500L (80hp, not available in USA). So there is hope for people that want to hot rod their Elio. VW has a 3 cylinder too. I have high expectations for this Elio motor(reliabilty, mpg).
Three cylinders are more dynamically balanced and most dont need balance shafts like 4 cylinder engines do. With todays engine control techonolgy, you can get lots of horsepower and or efficiency out of very small engines.
Small engines will always have the issue of thermal efficiency. There's just more surface area per volume in them. The Elio is mitigating that by using their cylinder coating. Apparently racing has used spray ceramics for quite a while, but 100k durability isn't as important there. So I'm sure the Elio is better for durability just ahead of thermal improvements.