If you have been looking for a tuning box for your car you might have noticed claims by some tuning box manufacturers that their tuning box can increase the power of your engine and also improve the fuel economy.
Quite rightly, you may be asking “how can that be possible?!?!”
Obviously you can not go faster and save on fuel so how can the tuning box manufacturers claim their product improves fuel economy?
Unlike the power gains which are dependent on the product, the fuel economy gains are completely dependent on how the car is driven.
Fundamentally to get better fuel economy the engine needs to turn less revolutions over the course of a journey.
For example. Driving normally trip A needs 20,000 revolutions.
If you can cover the same trip but only turn the engine over 15,000 times, that is 5,000 less injection events from the fuel injectors. Theoretically you can save 25% in fuel by simply using less revolutions per journey.
Okay you may be saying but I don’t need a tuning box to use less revs so why would I buy it for fuel economy?
Because the tuning box will allow you to travel and accelerate at the same rate as before because it increases the torque of the engine. Whereas before you may have needed to rev the engine to 4000rpm to get the acceleration you need, with a quality tuning box you can use less rpm and still achieve the same rate of acceleration.
And that’s it.
Because you get more power and less rpm, a tuning box allows you to turn the engine over less times per trip and therefore saves you fuel.
As I said at the start, the fuel economy figures are completely dependent on the driver, if the driver uses the extra power of the tuning box to accelerate faster and/or to travel at a higher speed, fuel economy will decrease, a tuning box is not a miracle device!
Something else to bear in mind is where you drive. If you drive on a motorway, your cruising speed will probably be the same, with or without a tuning box and the gear you use will also be the same. In this case the revolutions you use will be the same, with or without a tuning box.
To see the benefits of improved fuel economy, your journey needs to involve acceleration and braking ie driving in town and/or country roads. Fuel economy on motorways/freeway/autostrada will probably be the same with or without a tuning box for the reasons mentioned above.
If you were wondering about the fuel economy claims of the tuning box manufacturers, I hope this article has clarified the issue.