Inside any factory ECU is a map that it follows and when the engines rpm, throttle position and load changes, it is the ECU that is responsible for adding the correct amount of timing and fuel in order for the vehicle to run as smoothly and economically as possible.
A re-flash is simply exactly how it sounds, replacing the factory or existing map with a new one to suit your application.
Custom dual map tuning can be applied to most mid to high end engine management systems with dual map capabilities.
All of the big manufacturers such as Haltech, MoTeC, Microtech, Autronic and EMS offer multiple map computers within their range which we are able to switch between maps in an instant.
Having two maps in the one ECU, switchable by the push of a button can be used for the following.
One can be a street map tuned for good fuel economy, while another can be a more aggressive race map.
More examples:
Pump fuel vs Race fuel
98OCT vs E85
E85 has quickly become the choice performance fuel, costing almost a tenth of the price of an off the shelf race fuel. With an octane rating of between 107-110, the fuel consisting of 85% ethanol and 15% petrol has some great advantages.
* Cost
* A cooler burn rate resulting in lower exhaust gas temperatures
* Significantly less CO (carbon monoxide) and HC (hydro-carbons) from the exhaust making it far better for our envioronment than petrol
* Greater knock resistance
* Stable water temperatures
E85 burns faster, requires additional fuel, bigger injectors and commonly, a fuel pump upgrade.
This also means that the fuel economy is effected. What you lose in fuel economy is levelled out by the price of the fuel. Race fuel on the pump at $1 a litre? Nothing can beat that!