With diesel engines, the compression ratio is higher
and there is more power. From a technical point, the
compression ratio of an engine is the comparison of the
total volume of the cylinder at the bottom of the
piston’s stroke divided by the volume of the cylinder
remaining at the top of the stroke.
Serious damage to gas engines can occur if you attempt
to run a high compression ratio with a low octane type
of fuel. Detonation is the ignition of the fuel due
to the high temperature caused by a high compression
ratio that is developed by design. The fuel is
ignited prior to the spark of the plugs that result
in a rapid, yet uncontrolled burning.
Keep in mind, the diesel is a heat engine, using heat
developed from the compression of air. High compression
ratios are possible since the air is compressed. The
hot compressed air is sufficient to ignite the diesel
fuel when it’s finally injected near the top of the
Fuel and air in the design of diesel engines are not
premixed outside of the cylinder. Air is taken into
the cylinder through the intake valve and then
compressed to make heat. The diesel fuel is injected
near the top of the piston’s stroke in an amount or
ratio that corresponds to the load on the engine.
The higher compression ratio causes engineers to
design, and test the block, heads, head bolts,
crankshaft, connecting rods, rod bolts, pistons,
piston pins, etc., with a greater range of structural
capacity. To put it in other terms, diesels are
heavier than gasoline engines.
Deciding on gas and diesel can be tough, although there
are several reasons why you should use diesel.
1. Diesel engines produce twice the power
per gallon of fuel than gasoline.
2. A gallon of diesel is normally cheaper
than a gallon of gas.
3. Diesel fuel doesn’t blow up. The fact
is, its hard to get diesel to burn at all.
4. Diesel engines will last four times
longer than gasoline engines.
5. Diesel fuel that is untreated will last
longer in storage than untreated gasoline.
6. Treated diesel fuel will last longer in
storage than treated gasoline.
7. Diesel fuel treatment will cost less
than gas treatment.
8. Spoiled diesel can be reconditioned to
refinery specifications, as spoiled gas can’t.
9. Unmodified diesel engines can be run on