Road Mapping or Dyno Mapping … which is best ?

A much written about subject for sure but one that keeps getting asked of me when out and about mapping cars. Hence why this page …

So lets take each one on its own:

Road Mapping

Obvious really but mapping on the road has distinct advantages and some very big disadvantages. Taking the advantages first:

  • it is very convenient to the customer (and often the mapper)
  • can map almost anywhere in the world
  • lower cost as not paying dyno hire charges
  • calibrate the car based on feel and correct data rather than chasing power figures
  • the car is driven in the real world and as such mapping in that real world means the map would be tested in its proper environment


  • often involves driving ‘spiritedly’
  • potential danger of and to other road users
  • road conditions such as rain, snow or traffic don’t allow proper safe mapping
  • the experience of the driver may also cause issues when following instructions
  • there are no exact power figures produced (road dynos are notoriously inaccurate)

Dyno Mapping

The dyno is a controlled environment specifically designed to make remapping and measurement of power as safe and effective as possible.  There are many different makes of dyno and each has its own pros and cons but they are a great tool for tuning if you don’t take the figures as 100% right… they are best used to show improvements and ultimately the way the car drives is the real test. Dyno software automatically adjusts for temperature and barometric conditions and as such the power a car produces in winter should be similar to what it will show in mid summer. (however a word of warning these same compensations are open to abuse by some dyno centres though)

So … advantages:

  • safe for driver, safe for mapper and safe for other road users
  • safe for the car as, at the dyno centres racedynamix uses, the fan set up is optimised for recreating the flow of air experienced in the real world and whilst being fulled monitored during calibration it is much easier to spot potential failures
  • you can map every single area of the map without having to wait for perfect road conditions or space in traffic
  • identifying issues with the car is much easier when potentially you can view the engine whist it is under extreme load (things such as hoses collapsing is easy to see on the dyno)
  • also, exact power, torque and other graphs are produced which are useful down the pub 😉 and indeed useful to show progress in performance
  • with experience of remapping various cars, it is possible to fully recreate real world conditions and driveability on most dynos

RaceDynamix will map on either the road or the dyno but where customers are within major cities it is often impossible to find suitably safe roads to map on within a close enough area and, in these cases, dyno mapping is a must.

RaceDynamix has regular arrangements to use dyno centres around the country.  These are marked on the map above and show where regular dyno mapping are carried out. We have no distinct preference and it will often be dictated by the power potential of the car (over 400bhp and it should be done on the dyno), and the owners wishes.  However, the dyno is a great tool for getting the best possible map on your car and the extra £75 or so required for hiring the dyno is well worth it.