Which.co.uk/cars/driving/driver tools/litres to gallons converter

Test score. Our free tool converts between litres and gallons, so you can see exactly how much fuel it takes to fill your tank. Martin Pratt. Share on Facebook Share on Twitter Share by email. Latest News In Which? Crash tests: which electric car is safest to drive? Brake horsepower — or bhp — is the most widely used measure of engine power alongside PS see below , although it's often not clear which unit manufacturers are using in their brochures.

It's measured at the road wheels, not at the flywheel. Powerful engines have a higher bhp figure. For example, an entry-level Toyota iQ has a 68bhp engine, while a supercharged Jaguar XF packs bhp. We review all types of cars including city , electric and estate cars best sports cars. One PS is about You may see some carmakers quoting the power of their engines in kilowatts — especially on the continent — but this measurement is used far less frequently than PS or bhp.

A kilowatt kW of power equates to around 1. Torque refers to the amount of pulling power an engine delivers when working at different speeds. The more torque an engine has, the more pull or acceleration it offers at lower revs. In our lab, we look at how economical cars are in a range of scenarios: driving around town, out of town and on the motorway.

We also present a 'combined' figure, which is a weighted average of these scenarios. Developments in hybrid technology mean that petrol-hybrids are slowly catching up to diesel on motorway fuel economy. Given these averages, the around town and combined mpg will be more important to most people, making hybrids the clear winner see table below. As petrol is cheaper than diesel to buy, it's a bit of a double whammy given that the most efficient type of car - petrol-hybrids - uses the least costly fuel.

This helps to makes petrol-hybrids substantially cheaper to run than petrol or diesel. It's important to note these figures do not include plug-in hybrids or mild hybrids due to numbers tested across different car classes, just 'full hybrids'. Anybody looking to buy a car needs to understand the differences between these types of hybrid and why it's important. Happily that's exactly what we explain, plus give a rundown of the best hybrids available, with our guide to the best hybrid cars you can buy.

If you're a Which? Not yet a member? You can try Which? You will also unlock all of our online reviews, including our expert car reviews. Hybrid fuel economy is at its best when driving around town. But on faster roads such as on motorways, hybrids rely more on their combustion engine which diminishes fuel economy. However, as hybrid technology evolves, we expect to see more cars with improved overall and motorway fuel economy. As you can see above, some hybrids are already getting there.

Which means there will be ever-diminishing reasons to buy a diesel car. But while hybrids can offer brilliant fuel economy, don't believe the hype around official plug-in hybrid fuel economy claims.

In official tests, they're able to offset their fuel economy results with the electric-only range, but to an unrealistic degree. Our tests also reveal how polluting a plug-in hybrid can be if you're not able to top up the battery yourself.

Read more about about our research, hybrids and which models we recommend by heading to our page on the best hybrid cars. You can use our simple fuel-cost calculator, below, to easily work out the fuel costs between two cars. Enter the respective fuel-economy figures for the cars and your mileage to see the difference. For the most accurate results, don't use the manufacturers' claimed figures. Current fuel prices can be looked up on sites such as TheAA. You might be surprised to find out that a car that has two methods of propulsion would be less problematic than a car with just a combustion engine, but it's true.

Every year, we ask people to complete the annual Which? We gather details on what faults owners encountered in the 12 months prior to answering our survey. We find out what faults occur and reoccur , how severe the faults are, breakdown rates and the time required for cars to be fixed, among other information.

In our most recent survey, 47, owners told us about 55, cars that they own. The figures are very clear: hybrid owners suffer fewer faults and breakdowns. The faults that full hybrids do have are, on average, less severe than the average fault suffered by petrol and diesel cars. Which subsequently means they require less time off the road to be repaired. We don't yet have enough data to be able to report on plug-in hybrid cars as, like electric cars, they're still establishing themselves.

But the more people who buy them and feedback in our subsequent reliability surveys, the clearer the picture we will be able to present of how reliable, or not, these cars are.

Find out more about why hybrid cars are more reliable, how they differ from electric cars and what are the best hybrids you can buy right now by heading to our pick of the best hybrid cars. Latest News In Which?

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