We only do the first option. The strong advantages of a remap vs. an additional box are that a remapping is invisible, it does not generate optimistic mileage figures on the On- board computer (an additional box fools the original system) , plays will all the engine parameters available (where an additional box will typically only focus on quantity of fuel, allows to remove speed limiters and will systematically provide better results(the best additional boxes only bring up to 50% of what can be achieve with a good remapping). Nevertheless, in some rare cases, we do use PROGRAMABLE (hence very advanced technology) additional boxes. In this case, this technology is as effective as remapping and allows us to perform power enhancements on engines ECUs that are not yet « cracked ».
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