Are you suppose to retune your A/F ratios

[baynsac]

Are you suppose to retune your A/F ratios for the increased flow made by the I/H/E?? I read somewhere that you should retune your Afr's when you add exhaust, headers, intake and it makes sense to me but how is it done?
If so how?
Thanks

 

[SWIFTVISION]

Your stock ECU does this for you.

 

[baynsac]

Are you sure? No need to reset anything to make it adjust?
Thanks

 

[SWIFTVISION]

If you want to reset the ecu....pull the power off the batt.....let it sit for a minute, step on the brake pedal......hook up the battery again.....turn on the car....do NOT touch the gas....let it ideal till it reaches normal operating temps....turn off the car.....restart it, and your set.

 

[Larry Bastanza]

If you want to reset the ecu....pull the power off the batt.....let it sit for a minute, step on the brake pedal......hook up the battery again.....turn on the car....do NOT touch the gas....let it ideal till it reaches normal operating temps....turn off the car.....restart it, and your set.

So what is the point of this procedure?

All you need to do is pull the 7.5amp clock fuse for 10 seconds and the ECU is reset and all the fuel trim data is cleared.

Regards,
LarryB

 

[L8apex32]

Are you sure? No need to reset anything to make it adjust?
Thanks

Correct. The ECU has tables it uses to look up a/f ratios... but then it uses the info from the O2 sensors to fine-tune the numbers. It records the adjustments from the hard-coded values in other tables. The ECU is constantly tuning itself to recent conditions so there is no need force it to forget all it has learned... its constantly "adjusting" anyway.

You know the idea of "bolt on" performance parts? Part of the idea of bolt-on is that the ECU can handle the change and you don't have to move to a re-programmed one or even a programmable one. Contrast to changing compression or displacement - not a bolt-on change.

ECUs are pretty smart.
Your mileage may vary.