Economy tuning on a van that does 30,000 miles a year

Where the saving comes from

Not from using less fuel for the same work — physics does not allow that. From letting the engine do the same work at lower revs, where it is more efficient.

More torque low down means a van holds seventy in top rather than dropping a gear on every incline. Fewer downshifts, lower average revs, less fuel.

What it is actually worth

Realistically five to ten per cent on a van doing motorway and A-road mileage. Less in town, where the engine is rarely in the part of the range being improved.

On 30,000 miles a year at current diesel prices, the middle of that range covers the cost of the remap within the first year and keeps paying afterwards.

Below about 12,000 miles a year the arithmetic stops working, and we will tell you so rather than take the booking.

The driver matters more than the map

A heavy right foot will erase the entire gain. We have seen two identical vans from the same fleet, mapped the same day, return figures nine per cent apart.

If you run a fleet, the map and a conversation about driving style together are worth far more than either alone.

Doing it across a fleet

The priority changes. Consistency beats maximum gain: every vehicle mapped identically so a driver moving between vans notices nothing.

Above three or four vehicles we come to the yard and invoice monthly, which keeps the vans working instead of shuttling them one at a time.

How to know it worked

Not from the dyno — that measures power, not consumption. From your own tank-to-tank figures over a month, on the same routes.

Take a baseline before you book. Most people do not, and then have no way of answering their own question afterwards.

Loaded is the case that matters

Most vans are tested and reviewed empty. Almost none of them work empty. A vehicle carrying most of a tonne behaves like a different machine, and that is the condition a van file should be written for.

Loaded, the engine spends far more time in the part of the rev range where a remap does its work, which is why the improvement is more noticeable on a working van than on the same van driven home at the weekend.

It is also why we ask what you actually carry. A parcel van and a plant van doing identical mileage want different files.

A van file written for an empty van is written for a condition the vehicle is almost never in.

Servicing gets more important, not less

A remapped van doing thirty thousand miles a year is working harder per mile in a way that shows up first in the oil. Stretching intervals on a tuned commercial is the single most common way owners turn a saving into a bill.

Nothing exotic is required — servicing on schedule with the correct specification oil is the whole of it. But on schedule means the manufacturer schedule, not the one that fits around a busy quarter.

We would rather say this before taking your money than after a turbo fails at ninety thousand miles.