One last comment...

Basically the other interesting fact my comments lead to is...

Each time you pay for a Gallon of gas, at best only 20% of the actual potential energy in that gas is used... the rest is wasted...

So if you pay $2/Gallon... You could almost say you are getting 40c of gas energy and burning $1.60 for nothing...

Such is the Internal Combustion engine... (A glow engine is a bit different obviously...)

Phew...

Matt