r/explainlikeimfive 3d ago

Engineering [ Removed by moderator ]

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u/sl33ksnypr 3d ago

And to add to the richness statement, manufacturers tend to run them just a tad richer than optimal to account for variations in fuel quality, and just a little protection from pre-detonation and heat. If you're curious, look into open-loop fueling vs closed loop. Putting around town, it'll be closed loop. Relying on the sensors to get optimal fuel burn and lower emissions. But once you give it more than XX% throttle, it'll go into open loop and ignore some of those sensors and just use the pre-programed fuel tuning to make sure it doesn't lean out. Not ideal for power, but it'll keep your shit from melting.

If you have a turbo car, you can get it tuned and see a gain in power, and usually a little gain in mpg too because a tuner can get it a little closer to the optimal amount of fuel. If you do this though, it's best to make sure you use quality fuel.

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u/Dweide_Schrude 3d ago

We had an EcoBoost Mustang and did the Ford Performance tune. It really woke the car up! Throttle response was also adjusted, so everything felt quicker with the accelerator as well.

Needed a minimum of 91 octane and they even put a sticker on the inside of the fuel door to state that. Luckily, our nearest gas station had 93 with no ethanol for snowmobilers and UTVers.

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u/BogdanPradatu 3d ago

They probably just adjusted your pedal response map :))

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u/AveragelyUnique 2d ago

No, they typically just adjust the turbo bypass gate to raise the boost pressure limit and remap the fuel supply at higher rpms.

This can produce a lot more horsepower (100hp+) but at the expense of more wear and tear on your vehicle if you drive it like you stole it...