How to Improve Your Fuel Efficiency

This guide explains how to improve the fuel efficiency in your vehicle, to help you get more mileage from a tank of fuel. 

We’ll cover everything there is to know about fuel efficiency and how you can improve it, whether you’re looking to get more out of a classic car, a converted campervan, or just your daily driver.

With fuel prices rising in the UK at the moment, many of us are feeling the impact. So, let’s take a look at the simple changes you can make to help improve your vehicle’s fuel efficiency, and save some pennies along the way. 

Quick Jump to:

What does fuel efficiency mean?
Why is fuel efficiency important?
How can I improve my fuel efficiency?
How can you improve fuel efficiency in a classic VW?
Can you make a classic VW camper more fuel-efficient?
How can I improve fuel economy in my VW Transporter?
What's the fuel efficiency like in a converted campervan?
Summary: What makes the biggest difference in fuel efficiency?

Fuel efficiency just means how far your vehicle can travel using a certain amount of fuel. This is usually measured in miles per gallon (MPG), with higher MPG indicating a more fuel-efficient vehicle which uses less fuel to travel the same distance.

There are many factors that influence fuel efficiency, including how you drive, how well your vehicle is maintained, and even what you’re carrying inside.

Better fuel efficiency means you can travel further before needing to fill up again, which also means you’ll be spending less money on fuel.

Consuming less fuel also lowers carbon emissions and improves air quality, so it’s beneficial for the environment, too.

This is something which has become increasingly important in recent weeks as the price of fuel has risen dramatically, leading to many of us seriously assessing how, when, and where we drive.

There are many ways to improve fuel economy in any vehicle, but the biggest improvements will come from combining multiple methods.

Here are a few of the key ways to improve your fuel efficiency: 

Smooth, gentle driving has a big impact on fuel efficiency, as your engine doesn’t need to work as hard. When you accelerate harshly or apply the brakes suddenly, you’re using more fuel than you need or wasting all the energy you used to get up to speed.

To improve your driving habits, try to accelerate gradually, maintain a steady speed wherever you can, and look ahead to anticipate traffic lights or junctions so you can let off the accelerator and slow down naturally, rather than brake heavily at the last minute. 

Using higher gears and changing up as quickly as possible is another way to boost your MPG. This keeps revs low (around 2,000rpm), which helps minimise your engine’s fuel consumption. 

Vehicle weight is another factor that’s often underestimated. The heavier your vehicle is, the harder the engine needs to work to get it moving. Campervans are the prime example, with water tanks, bike racks, awnings, tools, furniture and equipment, the weight can quickly add up.

Taking out any unnecessary items will reduce vehicle weight and improve fuel efficiency – whatever you drive. Even small things can make a difference. Every additional 50kg can increase your vehicle’s fuel consumption by up to 2%.

External fittings such as roof racks can increase wind resistance as well as weight, reducing fuel efficiency by up to 39% at motorway speeds, so it’s always best to remove these when not in use. 

If your tyres are underinflated, they create more resistance with the road surface, forcing the engine to use more fuel to roll the car along the road. Keeping tyres at the correct pressure keeps the vehicle moving easily and improves your MPG. We recommend you check your tyre pressures regularly to maximise efficiency. 

Driving in stop-start traffic is one of the least efficient ways to travel because the engine is constantly having to work harder to accelerate again, burning more fuel.

So, planning your journey and choosing routes with fewer stops, or travelling outside of peak times can help to reduce your fuel consumption and keep your vehicle in better shape.

It’s also worth noting that engines run more efficiently once they have warmed up, so if you can avoid lots of short trips and combine them into fewer, longer trips, it can be much more efficient.

Using the air-conditioning (especially at lower speeds) places extra strain on the engine, which increases fuel consumption. Try to use it sparingly to improve your vehicle’s efficiency. At speeds under 50mph, it’s generally more economical to open your windows. However, when you’re driving faster than 50mph, it’s better to use your air conditioning, as the open windows create more drag.

Regular servicing and maintenance are essential for good fuel efficiency. Components such as spark plugs, air filters, and fuel filters all play a part in how effectively the engine burns fuel. For example, a clogged air filter can restrict airflow and cause the engine to use more fuel than necessary.

Clean filters and components in good working order all contribute to a smoother and more efficient vehicle.

The quality of the oil you use is equally important. Engine oil is designed to reduce friction between moving parts, allowing the engine to run smoothly. Using poor-quality or old oil can increase the resistance inside the engine, causing it to work harder and use more fuel.

Therefore, it’s important to change the oil regularly and ensure you use the right grade to maintain good fuel efficiency.

Surprisingly, even the exhaust system can play a part. A well-designed exhaust helps the engine to breathe properly, by letting the gases exit efficiently. If it’s too restrictive or poorly matched, it can reduce performance and fuel economy. 

As fuel prices continue to rise, it’s good to shop around to find the best deals in your area. Downloading apps like PetrolPrices (if you’re in the UK) can help you compare nearby fuel stations so you can find the cheapest place to top up.

Motorway service stations are among the most expensive options, so it’s best to avoid them if you can. Instead, try buying fuel at supermarket petrol stations, where prices are usually the cheapest.

While air-cooled VW engines aren’t as efficient as modern ones, there are several things you can do to improve fuel economy, from regular servicing to upgrading some key components.

Air-cooled VW engines use carburettors, which are responsible for delivering fuel to the engine. While these are simple, they’re not quite as precise as modern fuel injection systems, which can lead to inefficiencies.

Frequently servicing your air-cooled engine is crucial. Keeping spark plugs clean and gapped ensures proper combustion, and clean filters allow the engine to breathe correctly.  

Upgrading to an electronic ignition system is another way to help improve fuel economy. These units replace worn traditional points and offer a reliable spark which improves engine running and fuel efficiency. They also eliminate the need for maintenance, so you can save your future self some time, too! Here at Just Kampers, we stock a wide range of Pertronix ignition units, so be sure to take a look.

Your carburettor setup also plays a role in your VW’s fuel economy. Some engines use twin carburettors which, if tuned correctly, can improve airflow and engine performance.

Oil is especially important in air-cooled engines because it helps with both lubrication and cooling. Regular oil changes and choosing a high-quality product, such as Morris Oil,  is key for engine health and efficiency.

Here are some useful upgrades that can help improve your fuel economy:

Yes, it is possible to improve the fuel efficiency of a classic camper.

Classic VW buses like the T2 Split or Bay are heavier and less aerodynamic than a car, so they naturally use more fuel. They typically average between 18 and 25 miles per gallon, depending on the journey, engine, and other factors.

Weight plays a major role in camper fuel economy. Adding furniture, storage, and equipment increases the load on the engine, so it must work harder to move the vehicle. External installations such as roof-racks also add to the inefficiency of the camper, so it’s best to remove any unused items inside or outside the camper to keep it as light as possible.

One of the best ways to boost the fuel economy in a classic camper is to apply better driving habits. Maintaining a constant speed and ensuring you don’t push the engine too hard can make a noticeable difference. For example, driving slightly slower on the motorway (55 or 60 mph) can reduce the strain on the engine and improve fuel efficiency, without adding much time to your journey.

As with air-cooled cars, it’s important to service your classic camper engine on a regular basis, and use top-quality products such as Morris Oil to keep it running smoothly.

Ensuring your tyres are correctly inflated and planning your routes to avoid traffic are some other simple but effective ways to reduce your camper’s fuel consumption.

Check out these practical upgrades to improve fuel efficiency in a classic camper:

Modern VW Transporters, like the T4, T5, and T6, are significantly more fuel-efficient than their classic counterparts, often getting between 35 and 50 mpg – but there’s still room for improvement.

These modern VWs use fuel injection systems which deliver precise amounts of fuel directly to the engine, providing effective and efficient combustion. This, combined with modern engine management systems, allows the vehicle to constantly adapt and adjust to get optimal performance from the engine.

However, there are still a few things you can do to get the most out of your fuel.

Firstly, try to be mindful of how often you use your air conditioning. While it’s a great relief from those hot sunny days, it can increase fuel consumption by placing extra load on the engine. So, try to limit your usage, especially during long trips.

Secondly, focus on your driving style. Accelerating and decelerating smoothly, maintaining constant speeds, and using cruise control on long motorway journeys can help you get the most out of your engine.

Also, as with classic Volkswagens, regular servicing is essential for your Transporter. Modern engines heavily rely on components such as sensors and filters, so keeping everything in top condition will ensure the engine runs as efficiently as possible. Check out our engine service kits to find everything you need in one click.

And don’t forget to remove any excess weight from the van, too!

Take a look at these helpful upgrades:

Converted vans such as Mercedes Sprinters or Ford Transits typically average between 25 and 40 mpg. 

While these campervans offer plenty of space and comfort, the addition of kitchens, beds, plumbing and storage can significantly increase the van’s weight, which directly decreases fuel efficiency. 

These vehicles are also much taller than your standard car or classic camper, and are often fitted with roof racks, solar panels, or awnings, which increases aerodynamic resistance and forces the engine to use more fuel. 

To improve fuel economy in a converted campervan, try to keep builds as lightweight as possible, avoid carrying unnecessary weight (including full water tanks), keep your tyres inflated to the recommended pressure, and drive as smoothly as you can. 

You can check out the blog ‘What Are the Most Fuel-Efficient Campervans?’ from our sister company, Just Kampers Insurance, for a better idea of the kinds of MPG you can expect from different types of camper. 

Regardless of what you drive, the biggest improvements come from taking simple and consistent steps. Driving smoothly, keeping your vehicle well maintained, planning your journeys, and minimising the weight in the vehicle can have a great impact on fuel economy and lower your costs.

Whether you’re driving an air-cooled classic or a modern campervan, improving fuel efficiency doesn’t come from one single fix - it’s about the small steps working together. And when you get the balance right, you’ll find yourself saving fuel, spending less, and enjoying a smoother journey.