Little surge during deceleration

[olivenoire]

Hello
For an unknow reason I'm know able to drive perfrectly my wg from spring pressure to 1 bar. Great great great
until boost switch I need to solve a last problem

From time to time when I release gaz pedal and let the car decelerating from example 6000 to 2000 rpm, the k20 surge a little bit
This happens by itself without touching the gaz pedal, for sure!

After a log and a check at the map, I discover a big gap between row 2 and 3.
So some possibilities to me before modifying anything

Is it best to change the range from row 2 or 3?
Is it best to change (lowered) fuel value
Or is it best to reduce the gap of cam angle (in this case 10° at row 2 -35° at row 3)

[olivenoire]

Maybe I need to attach the log and map?

[Hondata]

Datalog would help.

Is the the VTC cleaning operation? This normally happens the first deceleration after startup between 2-4000 rpm.

[olivenoire]

It happens very very often while decelerating
i will try to calibrate the TPS but as far I remember ven with this it is always a problem

I've added the map and the log

[olivenoire]

And some others logs
Finally I saw it happens in low and high..

Hope it will help to understand and solve my problem

[Hondata]

Under advanced set the overrun cutoff values lower. They are all 20-30 KPa, set them about 10 KPa lower.

[olivenoire]

Hi!

I was afraid I need to fine tuning the row 1-2-3!
Thank you for your tip, I will set it 10kpa lower!

But I discovered some surge @5000rpm and those value are max 1875 low and 3000 high
Anyway I will try

regards

[olivenoire]

Some news
I've lowered ask requested
Not enough and lowered again.
Seems good, need to check.but seems good

Wonder what is the minimal value.
Wondering if with low value injectors does not continue spraying some fuel?

[Hondata]

The injectors will cut off if the TPS is 0%. The MAP cutoff is not really necessary.

[olivenoire]

After some test some very few surge around 2000 rpm

I will stay as it for the moment but I need maybe to lower one again

Unfortunately mabe because of hard testing and hot temp (30°C outside and 42°C IAT) I discover some micro cutting at high rev.
I need to check the spark plug, maybe too hao. I probably need a colder indice

I wonder if I will find some information here, about what spark plug to fit with a turboed k20 9:1 piston@11psi

[Hondata]

Heat range 8 resistor spark plug. Reduce gap from 1.1mm to about 0.7mm Tip style (copper, platinum, iridium) only affects life, not performance.

[olivenoire]

Ok great, will check some new spark plug this way

Thanks again

[olivenoire]

I reply to myself

i actually drive BKR8EIX from NGK
And because of micro cutting -> Is it a good to go heat range 9 or I have to stay heat range 8??

[Hondata]

For 11 psi heat range 8 is good. 7 (stock) would work as well.

[olivenoire]

I do not receive notification (need to check), sorry for late reply

I'be bought 9 in case i want to drive 15 psi
But obviously I need to reduce gap for 8

My surging problem last, even with lowered overrun cutoff low and high cam
I need to try to "calibrate" the TPS
But I really wonder if this problem is not a "premiss" of a failure either with TPS of maybe injectors
injectors becomes very noisy like a diesel :(

Will share some new log later