Hondata

There are 2 lean spikes whenever i shift as shown above.

From the log i estimated my gear shift to be around 0.5s.

What is a good overrun fuel cut delay time to eliminate these spikes? My current setting is at 180ms.

Please advise. thanks!

IT is normal to get a lean reading when you shift gears as you are no longer under load.

Then am I right to say overrun fuel cut only helps squirting fuel when decelerating to cool engine head?

How much delay would cause back firing?

You really do not want fuel spraying durring decel as it is not needed. It is shutting off as you can see in the datalogs.

I am trying to spray more and longer to cool the engine during deceleration.

Will this be bad for my O2 sensors?

It washes the oil off the cylinder walls and causes ring wear.

But does it really help in cooling the engine? I am using this map only for track.

Engine cooling is mostly moot when you have 70% leakdown.

What about a perfectly healthy engine?

He's telling you that washing the bores down will damaged the engine and negate any benefits.

I see.... thanks for the advice!