Leon lcb11211@swbelldotnet wrote in
:

1. The heat extracted by the radiator is blown straight back on to
the source. How does that work? LOL

Well, it's actually not. The source is the combustion chamber
inside the engine. The air blowing back from the radiator is
hitting the outside of the engine, seperated from the source
by the engine block and water jacket. And, in practice of course
most of the air goes under the vehicle anyway.

2. I'm not sure how electric fuel pumps work to day but in the 70's
and 80's many were submerged inside the fuel tank. I disassembled an
electric fuel pump and noticed that the fuel travels through the
electric motor including the brushes. How does the vehicle not blow
up when out of fuel but loaded with gas vapors?

Simple - no oxygen. As long as the tank is full of gas vapors,
it's not full of air.

With respect to passenger cars, none of them have a radiator
big enough to handle their peak power output. The designers
depend on the fact that drivers rarely ask for full power for
more than a few seconds (passing on a two lane road, stop light
drag races, etc). Semi trucks, which do need to produce peak
power for extended periods, have vastly larger radiators even
tho their power output isn't much more (360-430hp would be
typical).

And hence the extra electric fans that often continue to run after
engine is turned off. I can assure you that engines reach peek
operating temperatures more often when sitting in traffic in summer
heat than when putting out peek power. If it were not for those fans
every vehicle would be over heating when is stop and go traffic.

Well, we're kind of looking at two different things there. One
is the ability of the radiator to extract heat from the engine.
Passenger car radiators aren't big enough to extract all the
heat produced at full power.

The other is the ability of the radiator to reject heat to the
atmosphere. That is very dependent on the speed of the air
moving thru the radiator, and if there's no air movement it's
close to zero heat rejection. Hence the fan to produce air
movement while the vehicle is stationary.

Yamaha rates my bikes engine at 188hp (from 1 liter). It has
a radiator of 14" x 10". You wouldn't need a much larger
radiator for the typical small car.

Different set up altogether. The engine is more in the open and heat
is not captured by the engine compartment found on most 4 wheel
vehicles.

Not so at all. A sport bike engine is much more enclosed in the
bodywork than an automobile engine. It's different, of course,
if you're talking about a Harley or other bike with no bodywork.

And especially, the engine is not working nearly as hard as a similar
HP car engine lugging around 3000+ pounds and powering AC, which BTY
also contributes heat through the condenser, and vehicles that still
have PS pumps.

Well, any engine putting out a given horsepower is working just
as hard as any other engine putting out the same horsepower.
That's inherent in the definition of power. But I'll grant
you that at idle, a car engine is working harder than a bike
engine is.

John