Re-mapping stand alone ECUs

Re-mapping is the all time hot topic in the tuning world. As prices come down on stand alone ECUs more often enthusiasts consider resorting to them rather than re-mapping the OE ECU.

The argument that once the ECU is installed it can be mapped as often as one desires or as often as the modification change seems to be appealing. After all the software comes free with the ECU and eveyone has got a laptop in these days.

So far - so good.

since Diesel ECUs are still in the region of 3lakh and beyond the following discussion will focus on the petrol powered cars.

Okay, fitting in a stand alone sounds quite easy. After all the sensors to collect the data are already there unless it is a carburettor fueled engine. Even then it is quite easy to fit a MAP sensor.

When actually starting the fitting process of the ECU it becomes very soon quite clear that this is not a fitting process. Best is to discard the term fitting and rather call it tying it in. In some cases it will be engineering it in.

As cars get newer the can bus gets more complex. This means that the ECU is linked to the air con ECU, which in turn is linked to other processors throughout the car. Even clocks are part of it in the latest cars. This creates a new problem. To make sure that all creature comforts work the OE ECU needs cohabiting with the stand alone. This can be quite some hurdle depending on the car.

After solving all the problems to this point it is time to look at the actual mapping.

This is where it really gets tricky. being an IT specialists thinking with all the knowledge of processors etc will enough to do mapping is the biggest mistake to be made in mapping.

To do the mapping it is essential to know the engine one is dealing with. After setting the mapping points in the different tables the question is whether they are right. How do you verify this?

There is a number of ways to do this. As there is a lack of chassis dynos in India the only alternative is out on the road. This means that a lot of time needs spending out there, which will effectively run into months.

This is even the case when a map is chosen from a similar set-up.

Re=maps have many niggles and they are to be ironed out when the basics is sorted. Sorting the basics is making sure that the engine is neither under fueled nor over fueled. Ignition timing needs to be spot on too. When extracting maximum power then it is also necessary to consider fuel variation and some other parameters. Failing to do so will in most cases lead to engine damage that can be occurring ranging from months to virtually instantly.

Even when this is sorted, which might result in many outburst of anger and very frustrating months more work needs doing. One annoying thing is getting the warm running right. And after that a few more niggles will showc up and need solving.

All can be sorted, but it needs experience to be successful and even more experience to make the financial losses minimal.

Before anyone starts with installing a stand alone they should be aware that it will most likely take weeks if not months before the car is back on the road unless the person installing does it for a living for a long time.