Difference between AFR on dyno vs the street
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Difference between AFR on dyno vs the street
Anyone know approximately how much AFR may be off on the dyno(dynojet) vs AFR for the same tune on the street(NA). I've heard that the AFR on a dyno is approx .5 lower than on the street as the load is not as great on the motor.
If this is true, if I want 12.9 or 13.0 AFR for the street/track, I should tune it for 12.4-5 on the dyno.
So, is there any truth to this?
Thanks,
Mike
If this is true, if I want 12.9 or 13.0 AFR for the street/track, I should tune it for 12.4-5 on the dyno.
So, is there any truth to this?
Thanks,
Mike
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I have a wide band o2, on the dyno I am at 13.0 to 13.1. When on the street it goes to 12.5 to 12.6. As the speed increased it gets richer. I have a WS6 with the BGR ramair mod. I believe as the cars speed increases there is more pressurize air coming in and the MAF is reads more air an adding extra fuel.
To get the most out of your car you will need to tweak your tune at the track or street. Each car is different, so I would check it with a wide band 02 at the track or street.
To get the most out of your car you will need to tweak your tune at the track or street. Each car is different, so I would check it with a wide band 02 at the track or street.
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I also found the seemingly ironclad 'you'll run at least 0.5 point leaner on the street' wrong too. I run almost identical AF dyno/street... and found optimal power at the same tune as well-meaning the car made the most power and ran the fastest set up exactly the same.