Tuning Box vs ECU Remap – What is the difference?

A tuning box is a tuning box, they all operate is basically the same way but remaps from different companies can be vastly different.

Tuning Boxes – How they work

Generally on modern turbo diesel engines tuning boxes increase the fuel pressure which in turn increases the amount of fuel being injected into the engine. Tuning boxes do this without changing any of the factory software.

ECU Remaps – How they work

ECU remaps will change the factory software to increase the power of a turbo diesel engine. How they increase the power will vary according to the manufacturer of the remap or the tune of your engine or if you are having custom tune. And at the moment, this is basically the difference. Remapping gives you more flexibility than a tuning box. If you need it…

At it’s most basic level a diesel ECU remap will increase the fuel going into the engine and nothing else. The method by which this is achieved can be done either by increasing the fuel rail pressure and/or increasing the injector duration and/or altering injection timing.

However a remap can become much more involved than this and it may also change other maps inside the cars ECU, for example the Mass Air Flow map, the boost map, fuel mixture map, basically any map that is accessible inside the ECU. The more in-depth and the more customised the map the more expensive the map will generally be although I am sure there are firms out there charging high end prices for basic remaps!

The differences are becoming greyer

Up until now I have explained the difference between a remap and a tuning box as coming down to the complexity and customisation of the products. Basically a remap can change more parameters and it is much more customisable compared to a tuning box.

But this is changing and tuning boxes are becoming more and more complex.

Problems with remapping modern ECUs

As technology and processor power increases, it is getting more and more expensive to analyse the latest ECUs. It is becoming more and more difficult to alter the maps in modern ECUs because there are so many maps to look through. It is hard to identify what is what and what knock on effects there are if one section of the coding is changed.

And this makes tuning boxes more attractive to manufacturers/tuners who want to get more from an engine.

For example, if you can simply increase turbo boost by lying to the ECU, the end product will be much cheaper and quicker to develop compared to going through the code in the car’s ECU.

As technology advances tuning boxes are intercepting more and more signals until they reach a point where you could get rid of the factory ECU completely.

And this is where the lines are becoming blurred

At the time of writing this article, Nov 2017, tuning products for BMWs seem to be the most advanced in the industry. Various companies such as Schnitzer, Dinan and Burger Motorsports have tuning boxes which intercept a plethora of sensors allowing the the car to be “remapped” without actually changing the software in the car’s ECU. And this is where the line becomes blurred.

I can see a time in the not too distant future when a tuning box will intercept enough sensors and have cleverer enough software built it that you will be able to effectively tune an engine without altering any of the factory ECU software.

What will be the difference between a Remap and a tuning box in the future?

Probably just the nature of how the engine is tuned. A remap will tune the engine by rewriting the original factory software on the car’s ECU, whereas a tuning box will will tune an engine without changing the factory software at all.

And at a certain point we will be asking the question, if I am intercepting so many of the factory sensors, would it not be easier just to use a stand alone engine management ECU and completely free myself of the limits of the car’s ECU?


This page was last modified Nov 21, 2017 @ 2:36 pm

Richard @ StrikeEngine

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