What is the efficiency of a modern internal combustion engine?

Question

Expressed in percent, how efficient are modern internal combustion, gasoline automotive engines -- let's say a Honda or Toyota engine? Anyone have any idea? I am talking about the efficieny in terms of what amount of energy used goes to produce power, and what is wasted as heat, or friction, etc.
Thanks

Answer 1

The efficiency of energy produced from the heat generated by combustin is only about 30% for most internal combustion engines. That is not taking into account the mechancial efficiency losses.