Captain Avgas
Well Known Member
I am re-printing this posting of mine from the depths of an Eggenfelner thread to the General Discussions area at the prompting of several readers. They believe it might be worthwhile reading for those contemplating the purchase of an engine.
The oft quoted argument that auto engines are more advanced than Lycomings is totally misleading. And it is the one single argument that most encourages experimental builders (and mechanically illiterate non gear heads in particular) to instal auto engines.
In reality the zenith of the piston engine was WW2 when literally billions of dollars were thrown at engine development and massive research and development was undertaken by all the major protagonists.
Virtually every "innovative" development that appeared in auto engines decades later appeared on aircraft piston engines during WW2. I refer to multiple valves per cylinder, turbo charging, super charging, intercoolers, over head camshafts, etc etc etc.
The reason that the Lycoming doesn't have these features is purely because it doesn't need them. The Lycoming is not a dinosaur...it is a crocodile. It is perfectly adapted technologically for it's environment.
The Lycoming is not outdated because it does not have four valves per cylinder. It doesn't NEED four valves per cylinder. At a steady 2300 to 2700 RPM four valves per cylinder will not improve performance....it would simply introduce a greater parts count and increase risk of failure for no gain.
The same can be said of complex engine management systems based on the integrated circuit which runs your electronic fuel injection system on your car. Do I want, or NEED these things on my Lycoming at a steady 2400RPM...no way. What I want is a simple, mechanical fuel injection system and a dual ignition system with intrinsic redundancy (which implies 2 plugs per cylinder). Does a car engine give you this ?
There are now 3 major competitive players in the Lycoming/Lyclone market and they are all struggling to find any way to make any truly significant technical improvement to the basic engine.
The Lycoming is not an outdated product....it is a VERY REFINED product, and nothing else on the market in the horsepower range offers anything like the power to weight ratio or reliability (not to mention ease of maintenance).
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The oft quoted argument that auto engines are more advanced than Lycomings is totally misleading. And it is the one single argument that most encourages experimental builders (and mechanically illiterate non gear heads in particular) to instal auto engines.
In reality the zenith of the piston engine was WW2 when literally billions of dollars were thrown at engine development and massive research and development was undertaken by all the major protagonists.
Virtually every "innovative" development that appeared in auto engines decades later appeared on aircraft piston engines during WW2. I refer to multiple valves per cylinder, turbo charging, super charging, intercoolers, over head camshafts, etc etc etc.
The reason that the Lycoming doesn't have these features is purely because it doesn't need them. The Lycoming is not a dinosaur...it is a crocodile. It is perfectly adapted technologically for it's environment.
The Lycoming is not outdated because it does not have four valves per cylinder. It doesn't NEED four valves per cylinder. At a steady 2300 to 2700 RPM four valves per cylinder will not improve performance....it would simply introduce a greater parts count and increase risk of failure for no gain.
The same can be said of complex engine management systems based on the integrated circuit which runs your electronic fuel injection system on your car. Do I want, or NEED these things on my Lycoming at a steady 2400RPM...no way. What I want is a simple, mechanical fuel injection system and a dual ignition system with intrinsic redundancy (which implies 2 plugs per cylinder). Does a car engine give you this ?
There are now 3 major competitive players in the Lycoming/Lyclone market and they are all struggling to find any way to make any truly significant technical improvement to the basic engine.
The Lycoming is not an outdated product....it is a VERY REFINED product, and nothing else on the market in the horsepower range offers anything like the power to weight ratio or reliability (not to mention ease of maintenance).
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