Does anybody know about the above subject?

Ok, so here is my understanding and the gurus, Please correct me if I’m wrong.

In 99% of cases diesels do not have throttle butterflies, Thus meaning the engine consumes to same amount of air regardless of throttle position (obviously imagining the RPM doesn't change)

So the way we increases the RPM is to increase the amount of fuel the injectors are firing in. Thus richerning the mixture or lowering the AFR.

With this in mind is it actually possible to have a rich or lean diesel? Surly the rich it gets the faster it will spin???

The only way I can see possible of it to be rich or lean is when the engine is under heavy load and there isn't enough fuel to accelerate the engine??

Also I have been reading about diesel AFRs and that Diesel will ignite between 4:1-50:1

That being case does anyone know what AFRs you should see in different cases. i.e. Idle, Cruse, Hard acc, High RMP ect ect.

Thanks.