EFI, Alpha-N vs Speed Density fueling Strategies

[Ed Wright]

Originally Posted by Karl Owens

I have found the Alpha N makes the car more consistent. The MAP sensor senses barometric pressure when the key is on and the engine is not running and makes adjustments to the fuel map accordingly, also at WOT there really isn't a difference between Alpha N and Speed Density unless you ave a really restrictive throttle body.

I have not found that at all. If you see a big change in Baro using Speed Density, as I explained earlier, it won't use the same cels in the V.E. table. If you have the V.E. Table correct, it will correct back to the same air/fuel ratio unless you tell it differently.