If your EFI system has pre and post temperature and pressure sensors then the fueling depends on whether or not the sensors are continuously read or only initially read, as Tony has already said.
A Mass Air Flow sensor reads air mass continuously as the engine operates which gives you a huge advantage over speed density technology and allows you the freedom to go to high altitude like Denver or low altitude like Death Valley without the need to retune your engine. There is typically also an IAT1 (Intake Air Temperature pre-compressor) and sometimes an IAT2 sensor (Intake Air Temperature post-compressor) to map how much the blower heats the air (for proper fueling) but also for detonation control.
Hot intake charges are more susceptible to detonation than cool intake charges. If the ECU's software is smart enough to track the IAT2 temps it can be used to pull timing when IAT2 temps get too frisky. This becomes a big deal for blown gas engines. One of the most detonation sensitive fuels is nitromethane. For the proletariat enthusiast it is always good to know that gasoline is equally detonation sensitive in, yes, supercharged applications.
By now it should have popped up on most folks radar screens that blown gas needs good detonation detection and prevention system. Many but not all EFI systems provide some level of detonation detection. For the ones that do not (or do a poor job) there is an excellent detonation detection and prevention device available from
J&S Electronics. It is called The Safeguard and it is available in three different configurations to handle distributor ignitions, smart coils (near or on plug) and dumb coils (near or on plug).
The J&S device will detect knock and then pull timing from
just the cylinder than knocked and do it in real time before the next ignition event! there is absolutely nothing available from anywhere else that can do this today. The technology is relatively mature but because of complexity has never been commercially duplicated. It was developed over 40 years ago for turbo charged V6 Buick Regals. Even embedded EFI knock control logic does not perform this well!
This is a link to the J&S website where you can dig little deeper if you are so inclined, click here =>
J&S Electronics.
Do not get detonation detection and prevention confused with the blinking lights that flash when they think they see detonation. By the time you see the light and before you can react, the damage has already been done. The earliest detonation events are imperceptable to the human ear. You need technology to 'hear' them. Even more daunting the sonic signature of detonation can be elusive.
The J&S Safeguard System consistently catches all of it at inception and pulls timing before the next ignition event occurs. After the event the J&S technology begins to increase the timing at each ignition event until it 'hears' detonation again. When it does, it steps back from the brink and runs that one cylinder just shy of detonating. It does this in real time as the engine is running and for all eight cylinders independently.
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