The fuel economy wars in full swing, and automakers are on a mission to make their vehicles go as far as possible on a litre of fuel. It’s a noble cause, though one they’re probably also driven to pursue by the rising demand for fuel-efficient vehicles spurred by rising gas prices.

It’s why hybrids and electric vehicles (EVs) are all the rage right now. But while they may be among the least-expensive vehicles to run, their higher price tags – relative to comparable gasoline-powered vehicles – are a turnoff for some. So is the driving experience, which can feel artificial and off-putting.

Thankfully, carmakers haven’t forgotten those drivers unwilling to give up the familiar feel of a conventional gasoline-powered car. Most have simply added to their new vehicles (hybrid or gas-powered) some kind of efficiency-boosting technology: aerodynamic body pieces designed to cheat the wind; turbocharging; high transmission gearing to keep engine speeds low; and so forth.

For those willing to make the leap, there are diesel engines, which have improved greatly in performance and exhaust emissions since their last brush with popularity in the 1970s.

So which sorts of technologies and which engine choices are right for you? Using the Chevrolet Cruze – a diesel version’s just joined the lineup for the 2013 model year – as an example, we’ll give you a quick rundown of the tech found in each trim, and explain how those features affect a car’s fuel economy and purchase price.

While shopping for a new car, you’re liable to notice a pattern in pricing: as fuel consumption goes down, price goes up. The base model traditional gasoline-engined car in most compact car lineups is, of course, the cheapest, but also the least efficient.

The Cruze’s $15,000 entry-level LS model, for example, comes with a no-nonsense 1.8-litre, 138-horsepower gasoline engine and manual transmission standard. During our testing, it actually delivered better fuel efficiency than a similar Cruze equipped with the optional automatic. We got about 8.2 L/100 km city, 5.4 L/100 km highway with the stickshift.

Adding a turbocharger to a tiny engine is a popular way to better fuel economy without sacrificing any performance. Case in point: the higher-trim LT model Cruze gets a smaller-but-turbocharged 1.4-litre engine that not only makes the same 138 hp, but gives the Cruze a bit more go during acceleration, thanks to an extra 23 lb-ft of torque (bringing the total to 148).

Still waiting for the kicker? Despite that extra oomph, the 1.4’s fuel consumption estimates are actually better than the non-turbocharged – and bigger – 1.8-litre engine, delivering an estimated 7.8 L/100 km city and 5.2 L/100 km highway when equipped with the manual transmission.

Indeed, the LT costs more by about $4,000, but it does offer a reasonable compromise between power and fuel economy. It’s also better equipped, with more standard features than the (quite basic) entry-level LS.

Don’t let that “Eco” badge fool you — the Cruze Eco model is neither a hybrid nor an electric. It is, in fact, an LT model specifically tailored for optimal fuel economy, and a good example of the sort of super-efficient, loaded-with-gas-saving-tech special trims automakers are coming up with to satisfy buyers keen on a gas car that sips fuel.

It features low-rolling resistance tires to reduce road friction, has grille shutters and sits lower to the ground, making the car more aerodynamic and slippery against the wind at high speeds. Even the spare tire is gone (replaced by a tire inflation kit) to shed that extra bit of weight.

And while it gets the LT’s turbo 1.4 engine, the Eco gains a manual transmission specially geared to help keep engine speeds low and thereby improve fuel economy—so off-the-line acceleration suffers a bit as a result. But for an extra $1,600 over the LT, the Eco manages an estimated fuel consumption of 7.2 L/100 km city and 4.6 L/100 km highway.

Notably, both LS, LT and Eco models get the best fuel economy when equipped with manual transmissions; and given the popularity of automatics in this class, many Cruze buyers are missing out on the best economy this compact really has to offer.

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Generally speaking, diesel engines are built extra-tough to stand up to the higher combustion pressures they require, making them more expensive to produce; consequently, they cost consumers a little extra.

That’s something to keep in mind when considering the top-range Cruze diesel model, which features a 151-horsepower, 2.0-litre turbocharged diesel engine.

It doesn’t sound like a big deal, but a common perk with diesel engines is their abundance of torque; the 2.0 in the Cruze puts out an impressive 264 lb-ft of grunt, for example, while still managing a fuel consumption of just 7.5 L/100 km city and 4.2 L/100 km highway, making the diesel the most efficient Cruze in the entire lineup.

Unlike the other gasoline models, the Cruze’s 2.0 diesel is only available with an automatic transmission, and is the only engine that features direct fuel injection—a modern engine innovation that promotes more efficient combustion and increases power relative to the volume of fuel used. Indeed, that’s a lot of fancy tech in favour of fuel economy—but it’s entirely trivial if you don’t think it’s really worth the $24,945 price tag.

As the Cruze lineup shows, better fuel economy often commands a higher price tag, since the technology used to net that efficiency isn’t cheap to engineer. The “best” car for you really depends on how much you are willing to spend. Budget-wise, most consumers would be satisfied with a base-model LT or its equivalent, since mechanical simplicity usually means a lower maintenance cost, too.

But how much bang do you want for your buck? Consider the fact the turbocharged Cruze LT comes with a similar list of features as the diesel, but costs $2,000 less, even when equipped with the automatic transmission.

You’ll also want to note that turbocharged engines typically require slightly more frequent maintenance than engines without power-boosters. That goes for the diesel, too: it uses urea injection, which requires a small reservoir to be refilled periodically in order to keep the engine running at its cleanest. (If that reservoir is left to run dry, the car will keep running, but will not restart, if turned off, until it’s topped off.)

So does the fuel economy of the diesel and 1.4-litre turbo engines warrant their higher purchase and maintenance costs? Alone, we don’t think so; but with more power on tap, you might prefer their performance enough to justify the cost. As with any automotive technology, everyone has different tastes and needs, and it’s all about the price you’re willing to pay to get what you want.