Briefly... (Please let me know if its too brief)
The Map sensor DOES tell the ecu how much air the engine is using and where to look for fuel in the map. If the map says "open inj for 2ms" thats what it will do, even if that means lean runnning or borewash. The map based system does not change, but what will change is the fuel that is actually delivered. This is because a 4th dimension is used to process the delivery of fuel.
This 4th dimension is the lambda sensors input to the ecu to tell the ecu how much fuel is being used via exhaust gas monitoring. What this means in a nutshell is instead of the map sensor saying:
"We have 1psi add the fuel from the 1psi part of the map"
We now have an ecu that will add the fuel from the 1psi part of the map and then refine it constantly by looking at teh emissions, if its rich ir will reduce injector duration itself, its its lean it will increase injector duration, and it will do this constantly, ensuring the fuelling stays stoichiometrically correct. This constant monitoring and adjustment is called "Closed loop lambda control"
This system came into operation worldwide in 1992 with the introduction of catalysts to mainstream production cars. The catalyst requires the fuel mixture to be chemically correct at 14.7:1 AFR so it doesnt get poisoned and this is why the lambda sensor and closed loop operation was devised for household consumption. We have simply refined this system for use with far larger injectors than originally intended by Ford or Marelli and then retrofitted the system into cars that were never equipped with it.
Il copy and paste some of my operating instructions into here now that i give to customers after purchase of teh system so you understand when it is locked to closed loop operation:
The Evolution software in your ecu is closed loop lambda enabled for ideal stoichiometry under all level and light throttle conditions. If the following parameters are met or exceeded, the ecu will revert to conventional mapping at all times.
1) Rapid throttle movements.
2) Throttle angle above 60%
3) Overun conditions
4) Boost pressure above 4psi
5) Engine speed above 4000rpm
6) Coolant temperature below 70deg C.
At all other times the fuelling will be under complete lambda control for best emissions and fuel economy. Please bear this in mind to get the best from your new engine control software.
So as you can see above, once your running hard, you are under 100% conventional mapping techniques and control methods which has no bearing on the lambda control side of things at all.
All we have done in a nutshell is brought the old fashioned cosworth fuel system into line with more modern equivalents. Welcome to 2004 guys.
As for Costs.
Standard mapping cost for a YB is £500
Lambda software is £100 extra.
On top of this you need a decent quality lambda sensor installed to supply my software with your signal and the heater system wired into the fuel circuit. This can be done yourself or by us.
Closed loop boost control is a definate essay and il maybe do that later...
