Hi there! I have a pending project - rebuilding a 50-year old army truck. Actually, it's an amphibious 8x8 armored personnel carrier, but it's not the point.
The machine weights 14tons and is equipped with a 12-liter V8 engine, naturally aspirated direct injection diesel. Compression ratio of 16.5, OHV, peak torque 550Nm @ 1200RPM, peak power 180hp @ 2000RPM. Engine is free-flow: no intake restrictions, no turbo, no catalyst.
Because the engine was designed for military purposes it runs almost any fuel mixtures from kerosene to vodka
but suffers from poor fuel economy: around 70l/100km (about 3MPG) depending on fuel quality.
So the question is: how does one make such engine more efficient?
Subquestions:
- How would compression ratio change affect fuel economy?
- How does cylinder unitary capacity affect fuel economy?
- What is the main drawback of such engine - electronic injection should get it 15% efficiency, what else?
- What are other differences between this one and modern engines? We can assume Ford Power Stroke 6.4 as a good replacement option (electronic injection, twin turbo, exhaust gas recycling, catalyst, intercooled and aftercooled).
Other thoughts: engine and chassis lubricants, tires and lights will all be replace by modern ones.