This isn’t going to make any sense.
To my knowledge so far of cars, there are many kinds of engines. The biggest factor that dictates power and fuel efficiency is the cylinders, such as 4 cylinder, 6 cylinder, V6, V8 etc all the way up to 12 cylinder if you have a lambo or something.
A 4 cylinder is going to be more fuel efficient than a v6 because less cylinders = less fuel being used by the engine. But the caveat to that is you’re going to have less power.
Trucks are bigger and heavier of course but you can have a v8 truck and a v8 car. Does that mean that the trucks v8 is bigger? What’s the difference between those 2 engines?
My main question is kind of like this, if you wanted to go from a v6 to a v8, why not just have a v6 that is just proportionately bigger in size so that the amount of fuel that’s injected into the engine equals that of the amount going into a v8? Or why not have a 4 cylinder that’s like twice as big as a regular one? What difference would that make in fuel efficiency, hp, etc?
I don’t know anything about cars so I hope this made sense.
In: Engineering
You have some incorrect assumptions going in. The biggest factor in power is the displacement (total swept volume of all the cylinders) and the biggest factor in efficiency is the compression ratio.
A high compression 6 cylinder can be much more efficient than a low compression 4, and could have more or less power depending on the compression and displacement. A Formula 1 engine is only 1.6L (about the same as a small straight 4 in a car) but it can put out over 1000 hp.
A truck V8 is typically larger displacement than a car V8 (larger cylinders and/or larger bore and/or larger stroke).
What matters is how much fuel you can burn, which depends on how much air you take in, which is displacement. And how much power you can get out of that fuel, which is compression ratio.
You absolutely can have a v6 that’s proportionally bigger and has the same displacement as a V8. If they have the same compression ratio, they’ll have about the same power and efficiency (minus some more complicated effects related to the extra stuff to make the cylinders work).
The size/number of cylinders is mostly about smoothness (more is generally smoother) and speed (many small cylinders can go faster than a small number of big ones).
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