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Things I'm missing in the FiST vs things I like

alexrex20

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#65
My mistake. My car does have the rear lights. Lol this whole time I thought it didn't. Of course I'm an idiot because I replaced the incandescent bulbs with LED as soon as I bought the car.

What I meant was it does not have the fancy airplane style aimable lights

Sent from my SM-G950U using Tapatalk
 


OP
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Thread Starter #66
Ummmmm no. Most cars, especially turbo charged ones, run RICH from the factory because it's safer... just look at your tail pipes after 1,000 miles. They will have a nice layer of soot from unburnt fuel. And again, as long as a car passes emissions testing in any fueling maps it wouldn't matter and would be completely legal.
Rich is not stoic.
More NOx emissions are generated at stoic.
Running rich will cause lots of unburned fuel to enter the atmosphere, which is just as bad.
 


zanethan

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#67
Rich is not stoic.
More NOx emissions are generated at stoic.
Running rich will cause lots of unburned fuel to enter the atmosphere, which is just as bad.
That doesn't change the fact that our cars, and most turbo charged cars, are tuned to run rich from the factory.
 


OP
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Thread Starter #68
That doesn't change the fact that our cars, and most turbo charged cars, are tuned to run rich from the factory...
Under load.
When just cruising they run lean.
Perhaps the little overboost window, is when lean and rich overlap to stoic?
 


zanethan

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#69
Under load.
When just cruising they run lean.
Perhaps the little overboost window, is when lean and rich overlap to stoic?
You would need to ask a tuner about the specifics of the fueling map but our cars run rich far before the over boost point. At the minimum they run rich as soon as you get into boost (about 2000 RPM depending on the gear/throttle input). Turbocharged cars are tuned this way to prevent detonation which is caused by running lean. To be clear when I say rich I'm not suggesting the point where it s just dumping fuel into the atmosphere. I'm saying rich as in the computer sends more fuel into the cylinders than can be burnt per the oxygen content. The harmful emissions are then caught by the catalytic converter. One of the common complaints about going cat less is the constant smell of unburnt fuel.

Edit:
I read through some tuning threads and as I suspected, as boost begins to build the AFR drops to being a richer mix. At idle or cruising conditions the AFR is equal to the stoichiometric ratio. So to answer you, no our cars don't run lean. They either run at stoich or richer.
 


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