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Discussion Starter #1
Mods are listed in the signature.. Im running Perrin Stage 2 93oct tune, I cant view the tune in AP Race as its locked, but logs show that its more aggressive than Cobb's stage 2.. Slightly higher boost and more aggressive timing..

I have no means of logging/knowing AFR.

A buddy from work was following me the other day and said I was shooting flames getting off the gas after WOT.. WTF?

I def am loosing power because of running so rich and also wasting gas..

Is this normal? how can I fix this?
 

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My car shoots 4 foot flames and with no way to log/view AFRs... Running Pig Rich is a good thing.
 

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If he's running Cat-less his rear 02 is useless anyway and he doesnt have a cat to muckle. Run it rich bro
 

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More or less.
 

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Wait... so you're saying the primary o2, the o2 in charge of adjusting the fuel mixture is completely useless with you are running a test pipe? Cause, no offense to you guys, i find that pretty hard to believe.
 

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Discussion Starter #10
Running a test pipe folks. But that should make me leaner since stage 2 tunes are generally developed for hfc.
 

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I'm running a testpipe no problem with AFR

Wait... so you're saying the primary o2, the o2 in charge of adjusting the fuel mixture is completely useless with you are running a test pipe? Cause, no offense to you guys, i find that pretty hard to believe.
I don't know..lol guess that's why there's a thing called wideband:godance:
 

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Widebands are there to precisely measure the AFR. A working narrowband o2 sensor is capable of reading voltages you can roughly translate into an AFR number +/-.5 (being modest on that, many have gotten closer) of an AFR to a wideband. Plus, most widebands read AFR only, they don't tell the computer what to run and what not to run (stock ECU). So in that case, a narrow band o2 sensor is needed, and the test pipe does not hinder the function of that sensor. With that said, running rich (flames don't just mean rich) will foul out the narrowband o2 sensor and toss up a CEL.
 

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It's not that you're running rich, when you're at WOT and you shift, the engine is still dumping fuel as if you had 25lbs of boost up... So for a split second it dumps too much fuel and coats the inside of the exhaust. Exhaust valves open again and BLAMO.
 

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Nothing to do with rich or lean.

When you lift off the throttle pedal, the throttle plate gets closed. That cuts off almost all incoming air flow - and seriously decreases the manifold pressure (where it goes into high vacuum).

When the pressure decrease occurs, all the fuel (and other HC compounds) remaining in the intake track are immediately boiled and dumped into the next burning cycle - where it is often too rich to burn in the cylinder. So the unburned fuel goes into the hot exhaust system

Since the ECU shuts off fuel flow on closed throttle (when engine is above idle speeds) no more fuel in added while *some* air gets past the closed throttle (idle airflow). That air and the previous cycle's excess fuel is what burns in the exhaust pipe - where it's still hot enough to light it off.

And since there's no CAT to perform the post-cylinder burning, and lots more available oxygen towards the open of the exhaust system, flame is create.

Flame is good.
 

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Nothing to do with rich or lean.

When you lift off the throttle pedal, the throttle plate gets closed. That cuts off almost all incoming air flow - and seriously decreases the manifold pressure (where it goes into high vacuum).

When the pressure decrease occurs, all the fuel (and other HC compounds) remaining in the intake track are immediately boiled and dumped into the next burning cycle - where it is often too rich to burn in the cylinder. So the unburned fuel goes into the hot exhaust system

Since the ECU shuts off fuel flow on closed throttle (when engine is above idle speeds) no more fuel in added while *some* air gets past the closed throttle (idle airflow). That air and the previous cycle's excess fuel is what burns in the exhaust pipe - where it's still hot enough to light it off.

And since there's no CAT to perform the post-cylinder burning, and lots more available oxygen towards the open of the exhaust system, flame is create.

Flame is good.
:+1:

Im tuned professionally and shoot flames.
 

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Wait... so you're saying the primary o2, the o2 in charge of adjusting the fuel mixture is completely useless with you are running a test pipe? Cause, no offense to you guys, i find that pretty hard to believe.
The primary 02 sensor is located in the downpipe BEFORE the testpipe, this is the important one. The one on the testpipe, however, can be removed/disabled with no ill effects.
 

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My buddy is 12 AFR at WOT, with a testpipe, and he shoots flames.
 

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To answer your question as plainly as possible, this is perfectly normal. You'd have issues if you were shooting flames when coming off throttle at say 35% (that's a random figure, it really doesn't matter as long as your car is not ON fire).

And there is no simple fix other then don't go wot.
 

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then don't go wot.
:bowlol::bowlol::bowlol:

Anyway, Don't know who said it but running pig rich is NOT a good thing. Kills gas mileage and can lead to detonation. Sure lean isn't good either but stupid pig rich isn't either. That's why tunes are so important, to find that proper balance with mods.
 
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