datalogging vs dyno tuning

for those who are new to the tuning world, you may only be aware of the illusive magical unicorn that of which is the dynamometer.  i highly recommend that all prospective customers search the internet for discussions on said topic.

what i will share on this topic is the fact that more than 90% of dynos utilized today are inertia dynos, not load bearing dynos.  inertia dynos cannot and i mean absolutely can not allow for any self proclaimed "tuner" to tune anything further than full throttle operation.  the difference is, load bearing dyno's will allow for full load mapping across all load variables and rpm ranges to "simulate" real life road conditions.  they do this by providing a resistance against the vehicles operation to "simulate" on road conditions.  load bearing dyno's allow for this operation to be completed in a controlled environment.  this will allow the "tuner" to fully map fueling, ignition, boost, engine response, throttle pumps, etc per load variable within the engines computer.  datalogging allows us to serve this same purpose as load bearing as it is factual to the vehicle.  that being said, even load bearing dyno's have their downsides.  on average, your typical load being dyno unless setup in a wind tunnel cannot and will not have the ability to increase load based off air friction flowing across your vehicle thus increasing load.  this in turn will now allow for factual ignition mapping based off existing load variables.  they also cannot simulate the actual air flow across and through your engine inlets.  with this in mind in general, dyno tunes versus road tunes aka datalogging, will differ in acutla air fuel ratios by about 0.3 air fuel gasoline in respect to what was seen on dyno.

understand what you're buying and what is being sold to you.  from there make the best choice to suit your needs.