Quote:
Originally Posted by businessdude
As someone who leases cars, these words and concepts are foreign to me, but there must be some advantage to using an interference engine for Honda? Maybe cheaper to produce?
Weird - I never stopped to wonder why but your question made me look up the answer. (from the first google link so lets just assume this must be correct)
The main reason why is because everyone wants good engines. That means powerful, efficient engines, and one of the best ways to make powerful, efficient engines is to have engines with high compression.
Compression refers to how much the fuel/air mixture in an engine’s cylinders is, you know, compressed. The more you can squeeze that mixture, the more bang you can get for your buck, almost literally.
Compressing more, though, means pushing that piston further and further up into that cylinder—which means that piston’s top is very likely to reach the same places where the valves will be when open, which means that the piston and valves have the possibility of—you guessed it—interfering with one another.
This is also why nearly all diesel engines are interference engines—by their nature diesels are very high compression engines.
The benefits of high compression are so good that many engine designers decide it’s worth the risk to have an interference design. If you’re willing to change the timing belt or chain when the manufacturer suggests (usually starting around 60,000 miles or so, it’s not like changing oil or underpants) then, ideally, you really shouldn’t have to worry.