Honda once had a very successful F1 program with its turbo-charged engine.
That experience, cooling the engine with raw fuel, must have taught Honda
not to use turbo-charged engine in ordinary cars because of poor fuel economy,
dirty exhaust and expensive maintenance. Fast forward to 2013, now with
direct-to-cylinder fuel injection and precise valve and ignition timing control,
automakers can now use turbo-charging on their small engines without much
concern for compression ignition. With a modest 7psi boost a 10:1 compression
ratio engine turns, in practice, into a 15:1 engine. Yet, today some turbo-charged
engine can operate with regular gas.
The only concern for the modern turbo-charged engine is whether you can trust
something that turns as fast as 100,000rpm in the long run. At least it requires
more frequent oil changes.