do intakes lose power? do i need a tune? explained
Originally Posted by gsujeff55
yeah, i fixed it. car was going SUUUPER rich before it died(9:1), couldn't tune it out. SO, i pulled one of the springs from teh BOV and voila, perfect idle....and still holds boost.
Let me see if I can answer some questions in here. And, I know that this has been answered 1 billion times.
Fact: Change the OEM intake for a cone one (K&N, HKS, etc).
Hypotesis: Lose or Gain HP?
Conclusion: Lose HP in the overall area of you HP curve. But, why? Because your car is running leaner than 13.5 to 11.0 AFR* which is the optimum for your car to deliver max HP.
*=It is a range of values because it is a engine unique factor. I have seen same mods on the same car with different AFRs to deliver same HP.
Explanation: Why leaner with the cone filter?
In simple terms because the MAF was calibrated to be used with the OEM box that actually has some especific characteristics on how the air flow is coming into the compressor inlet. With the change of the filter, this characteristics change, now when the MAF sees X amount of air, it is really more air that is going into the compressor inlet causing the car to run lean. Hence, the need to re-tune your ECU to compensate for the extra air.
I work with different types of flow meters (liquid and gas) and every time you change a filter on the inlet or the diamater in the pipe is changed.... you need to recalibrate the flow meter. The engineering/mathematical explanation is because the reading in a flow meter is an estimate based on some constants (in our case air flow characteristics) that you are changing when you change the OEM filter. So, your new air flow estimates are now off and need to be recalibrate (re-tune ECU) so the ECU can now use the "right" amount of fuel. And, that is what we want at the end of the day. Right?
Hope this helps to some of you!
Fact: Change the OEM intake for a cone one (K&N, HKS, etc).
Hypotesis: Lose or Gain HP?
Conclusion: Lose HP in the overall area of you HP curve. But, why? Because your car is running leaner than 13.5 to 11.0 AFR* which is the optimum for your car to deliver max HP.
*=It is a range of values because it is a engine unique factor. I have seen same mods on the same car with different AFRs to deliver same HP.
Explanation: Why leaner with the cone filter?
In simple terms because the MAF was calibrated to be used with the OEM box that actually has some especific characteristics on how the air flow is coming into the compressor inlet. With the change of the filter, this characteristics change, now when the MAF sees X amount of air, it is really more air that is going into the compressor inlet causing the car to run lean. Hence, the need to re-tune your ECU to compensate for the extra air.
I work with different types of flow meters (liquid and gas) and every time you change a filter on the inlet or the diamater in the pipe is changed.... you need to recalibrate the flow meter. The engineering/mathematical explanation is because the reading in a flow meter is an estimate based on some constants (in our case air flow characteristics) that you are changing when you change the OEM filter. So, your new air flow estimates are now off and need to be recalibrate (re-tune ECU) so the ECU can now use the "right" amount of fuel. And, that is what we want at the end of the day. Right?
Hope this helps to some of you!
how the hell are you recommending up to 13.5 afr and how the hell do you figure that running leaner makes you lose hp? you might lose hp if you run leaner than high 11s but that's because your ecu pulls timing.
only na engines use high afrs and even then the highest you should have is around 12.8
please... i don't wanna be joed anymore.
only na engines use high afrs and even then the highest you should have is around 12.8
please... i don't wanna be joed anymore.
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