[Joeggernaut]

Stoich, is a ratio of fuel to oxygen that will allow fuel to ignite; now when it comes to modern engine controls; it depends on engine coolent temp, intake temp, map/maf, tps and o2.


Partially correct: It is ratio of fuel to air. Air consists of oxygen yes, but also carbon and hydrogen. Air is not the same as pure oxygen. Read about open and closed loop for how an engine matches stoich or whatever AFR ratio it is targeting.


most cold air intakes do not go down past the engine(because lower means water getting sucked up/hydrolocking/getting sued). "cold air" is subjective.

Wrong: Actually they do, people put sleeves over them to prevent hydrolock. You might be thinking of a SRI short ram intake which is different from a CAI.



most engines from the 80 and earlier had some variation of this, to help with cold start issues(too much oxygen to fuel). Still questioning why they got away from thermac's for fuel injection.

True


the only maf i've seen that interferes with airflow is the spoon type that ford used in the late 80's/early 90's

MAF systems use the same sensors to calculate air flow as the map does, just uses a different way to determine fuel; it's also an indirect method.



Wrong: All maf sensors are in direct line of air flow and do cause interference. The air has to move through and around the maf sensor inside the air intake. There is a slight decrease in efficiency because of this but is more accurate for the ECU as real-time data is calculated instead of in direct like a map setup. A Map sensor measures manifold air pressure and not air flow. They are two different setups but do share some of the same sensors but they are different.



nope, the camshaft profile is when it open's and how long it stays open per cycle.
LIFT is how far the valve opens and closes

Wrong: camshaft profile controls how far the valve opens and closes, same thing as lift, not duration. It only hits the lobe once, for it to stay on the lobe the camshaft must be advance or retard which is what camshaft phasing is.


Camshaft phasing is the change of camshaft timing in relation to it's static position; does not change duration


Wrong: What do you think camshaft phasing does then? You just said it yourself it changes timing which is the definition of duration. You are getting your definitions confused between phasing and profile.


might want to read this

AutoZine Technical School

Cool article, but I already knew what it does/is. It might be helpful to other readers who want to see visuals.


nope; duration doesn't change, phasing a cam changes when it opens and closes(eg crankshaft rotates 720 for every 360 of the camshaft; phasing means a camshaft the opens at 208 normally would move 10 or more degrees +/- so 208 could end up phased at 198 or 218 depending on the computer)

Wrong: Once again you are contradicting yourself by saying duration doesn't change. Phasing a cam means the cam is able to maintain that lobe profile longer or shorter which is the definition of duration/timing.


Do you have any input/idea off a WAI on new techonlogies as the thread was intended?