#How to reduce fuel consumption with a chiptuning unit

14 / July 2022
How to reduce fuel consumption with a chiptuning unit

Seletron Performance

How do chip tuners reduce consumption?


Today we want to talk to you about a topic that might be of interest to you. In over 20 years of experience in tuning diesel and gasoline cars, we have received this question hundreds of times, "How do additional chip tuners reduce fuel consumption?" We have often answered it in a rather practical way by recounting the testimonies of many of our customers. Now, however, we want to get a little bit more technical by talking about the factors that enable this rather counterintuitive benefit.


Many people wonder how it is possible that diesel or gasoline consumption can be reduced by increasing power. Let us first specify one important thing. Absolute consumption is not reduced; this is not possible. To get ten horsepower, you have to burn a certain amount of fuel (be it gasoline, diesel, CNG, etc.); to get twelve horsepower, you need a proportionately greater amount of fuel; this is to say that a fully exploited engine, if more powerful as a result of electronic tuning, will consume more in proportion to the increase in power. However, in factual reality, this is not exactly the case. In normal use, the engine is not exploited at full power all the time, which is why there is room for optimizing fuel consumption, especially if the driver knows how things work and is careful about how they use the accelerator pedal and the gearbox.


One of the main factors that make it possible for many people to reduce their fuel consumption is that the chip tuners increase torque in almost all cases, even at low engine speeds. On average, this allows greater use of the high gears of the transmission, especially in a manual car, where the driver makes use of the gearbox with this intent. To give an example, an uphill road can be driven with the original engine in second gear, while after electronic tuning, it could be tackled in third gear. What changes? The active power of the engine to overcome a given slope is always the same; suppose 40hp is needed, and the power required to travel uphill is the same before and after tuning, but in the first case (original engine), the power to the wheels is coming through a higher engine speed with less torque (expressed in Nm). In the second case, the power will come at a lower engine speed and higher torque. The product, rotational speed x Nm (thus the power), does not change, it is still 40hp, but the lower rotational speed brings some advantages:


Reduced energy losses from the coolant pump

Reduced energy losses from the lubricant pump

Reduced energy losses from the vacuum pump

Reduced energy losses from the power steering pump (if hydraulic)

Reduced energy losses from the alternating movement of masses

Reduced losses from exhaust gas back pressure


These are the main areas in which it is possible to actually achieve a reduction in engine energy losses resulting from a lower average engine speed. Then there are other phenomena (in turbo-diesel engines in particular) related to different balances between boost pressure and injected fuel quantity, parameters that are contained in engine management ECU maps, and that can vary engine efficiency.


Our chip tuning additional unit intervenes on various parameters depending on the type of electronic engine control system that is installed in the specific car. Regardless of the car type, the amount of diesel or gasoline injected and the boost pressure is managed. More vigorous injection at low engine speeds, plus the increased torque even in the absence of turbocharging (at least in turbo-diesels), can advance the turbocharger's ability to generate pressure by a few hundred revolutions due to a greater amount of exhaust gas resulting from the increased fuel injection.


In addition to the greater maximum torque obtained, these phenomena enable the engine's high gears to be used more to pick up speed and overcome inclines. Depending on the type of engine and especially the kind of driving, significant reductions in fuel consumption can be found in normal vehicle use.


In the case of exploiting all the available power, as stated from the very beginning of this article, one cannot expect lower consumption. That would be like expecting a 190hp BMW 2.0d at full power to consume as much as (or even less than) a 150hp BMW 2.0d also at full power. It is possible (but not certain) that the two BMW 2.0d engines will have the same consumption at a constant speed of 100Km/h since the reduced power they will deliver will be exactly the same.


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If you want to save on fuel costs, search for your car model in the catalog and check the availability of the additional CHIPBOX control unit >>> Choose your model here