Backfires while going WOT?

[Ninong]

Backfire can be in either Intake or Exhaust manifold.
Anything outside of the combustion chamber (uncontrolled)

Agree to disagree.

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[TJC]

Agree to disagree.

Back when I was a kid and wrenching, backfires (by definition) always came out the intake track up out the carb accompanied by a flame flash!

Wikipedia alludes to the confusion.

A backfire or afterburn is combustion or an explosion produced by a running internal combustion engine that occurs in the exhaust system, rather than inside the combustion chamber. It is also sometimes referred to as an afterfire, especially in cases where the word backfire is used to mean a fuel burn that occurs while an intake valve is open, causing the fire to move backward through the system and out through the intake instead of the exhaust. When the flame moves backward it may also be called a "pop-back". A backfire can be caused either by ignition that happens with an exhaust valve open or unburnt fuel making its way into the hot exhaust system. A visible flame may momentarily shoot out of the exhaust pipe. A backfire is often a sign that the engine is improperly tuned.

But I think the definition has changed a bit since then to cover both intake and exhaust, which BTW, are caused by entirely different issues.

Back in the 50's and 60's people actually wanted flames out the exhaust...

Hitting the rev limiter on modern cars can cause the issue. So can lack of back pressure.
Read on Others Comments...

"An engine can ignite fuel in the exhaust momentarily when the throttle is slammed closed at higher rpm. The sudden closure (restriction of air) creates a momentary rich condition and unburned fuel ignites in the exhaust. However this requires a fairly open exhaust system, usually no converters and straight through mufflers for the fire to actually exit the tailpipe."

"The old system used in the 50’s was pretty simple. You mount a spark plug in the end of your tailpipe and a small coil to fire it on command. You will also need to run a fuel line to the end of the tailpipe and a pump to get it there. You fire the spark plug and then give it a shot of fuel and you have flame."​

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Here's a How to link on creating flames out your exhaust.

"Anti-lag and two step are the same thing, and it's different from a rev limiter. Anti lag does limit rpm, but not by cutting ignition, but by delaying it. Essentially, the cylinders still take in a full fuel charge, but it's ignited very late. This means that it doesn't have time to fully burn before the exhaust valves open, so very little power is made (and therefore it limits engine speed). This still burning fuel/air mixture is sent out the exhaust, where it continues burning, and increasing in pressure. This drives the turbocharger to spin faster, therefore reducing lag. You can get the sound and flames without a turbocharger, but it's pretty pointless. It also causes exhaust components to experience much more heat and pressure than they were designed for. And if your car has a catalytic converter, it will fail very very quickly."​

 

[airline tech]

I posted a PID Data Ref here

Engine PID Data- Fuel Trims and Related | 2019+ Ford Ranger and Raptor Forum (5th Generation) - Ranger5G.com

 

[TxOTRRanger]

It was designed to be "normal" but the tranny couldn't identify with that and left the party...

...to finish that for everybody in the world of Automotive Chaos.
Because ROADKILL! Lol

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