FINALLY discovered the meaning of "Alpha - N"

[67Dart273]

Finally came across the basic definition of "Alpha- N" as applied to EFI

There are three basic major methods of electronic EFI

MAF or "Mass Air Flow" such as many Ford OEM This uses a mass air flow sensor to figure out the volume of air going into the intake, along with temperature and other sensors

"Air Density" used by some manufacturers such as Mopar and GM, and FItech, Holley, I don't know who all else

And then "Alpha - N" which I knew was simpler and used throttle position and engine RPM and probably air temp and little else

Evidently it means Alpha as in throttle ANGLE and N for "number" of engine RPM

 

[Stephen Hotz]

Ford started out as speed density but the problem was thier software could only work off set in stone parameters. For example a 302 could only move a maximum amount of air based of x camshaft, y intake manifold and z head. Mess with any of the above and the ecm could not calculate properly because the inputs were off the preset tables. Mass air changed that. A large portion of the oem's went to mass air as they could move to sequential instead of batch fire for fuel and emisions much easier.

 

[Treblig]

x camshaft, y intake manifold and z head, ecm, Mass air, move to sequential instead of batch fire for fuel. Sorry but it's all Greek to me.

Give me a car carburetor, a regular intake, regular gas, and I'm happy!!!

 

[RustyRatRod]

x camshaft, y intake manifold and z head, ecm, Mass air, move to sequential instead of batch fire for fuel. Sorry but it's all Greek to me.

Give me a car carburetor, a regular intake, regular gas, and I'm happy!!!

Yeah, me too.....and then you have some jerk givin you the disagree with no explanation. Happenin a lot lately.

 

[67Dart273]

Ford started out as speed density but the problem was thier software could only work off set in stone parameters. For example a 302 could only move a maximum amount of air based of x camshaft, y intake manifold and z head. Mess with any of the above and the ecm could not calculate properly because the inputs were off the preset tables. Mass air changed that. A large portion of the oem's went to mass air as they could move to sequential instead of batch fire for fuel and emisions much easier.

Always seemed to me that MAF had some advantages, but yet seems like most of the aftermarket, Holley, Megasquirt, FItech the list goes on..........are all speed density.

There is advantages to alpha n for lower speed wild cam applications it seems. Being able to switch from alpha n at lower RPM and "something else" later is the trick

 

[Stephen Hotz]

Processors have improved considerably. I would like to try out the AlphaN on a crossram dcoe style efi setup.

Something like this but think 383 with the filters plumbed into the hood on a 69 RR