Advanced Fueling Issue - Exhaust reversion?? - Need advice

[EEL]

Background info:

Intake mods performed:
K&N Air Filter
MWR Power up kit w/ green unifilter replacement

Exhaust mods performed:
SC Project GP-M2 slip on
Completely removed flapper valve from exhaust (this includes leftover bits inside exhaust after servo motor is removed)

ECU Mods
MW Flashed Rexxer to remove O2 sensors and servo and updated to a performance exhaust and intake map
PC-V
Autotune

ISSUE:
By running the autotune for my current setup I was able to determine that even the updated performance rexxer map was way too lean for the MWR power up kit. The bike pulled almost 30% more fuel at certain low RPM and low throttle positions because of the Power up kit. Autotune cured most of the popping but I still have some popping at:

1) From full throttle to zero throttle
2) From zero throttle to just opening the throttle up at cruise range (2% or 5%) throttle

This is what I need help with.

I think item 1 is exhaust reversion. But I'm not sure how to cure it? Dynojet generally says to leave the 0, 2% & half of 5% columns zero on the AFR table but considering the amount of open airbox present, I'm wondering if I need to go the other way and fill in the tables to a pseudo lean condition?

With the autotune, I can poke around to my hearts content but hoping I can get the braintrust to provide a clearer direction on how to proceed so that I can reduce the overall tinkering time.

[Dirty Duc]

Those transitions can be hard to trace without monitoring intake vacuum.  

Does it happen at all RPMs?  What do you consider "cruise range" RPM?

Exhaust reversion is unlikely to affect O2 sensors in the stock location with the rest of a system on.  We had issues at Bonneville that I blamed partly on there being something like an inch between the sensor and the end of the pipe.

[EEL]

Thank you for the insight.

It does not seem to happen at all RPM. I think its primarily low RPM throttle shutoff. It seems to kick in at around 5k to 2k with the throttle off. I will take a test ride and check it out

Aas for the the cruise. I am able to pinpoint that more specifically its seems to happen when I get off the throttle in traffic and then just barely get back on. RPM is about 3900 - 4100.

Bike pops lightly.

THe heavy popping is actually in the 1st condition.

[Dirty Duc]

Where do your 5% bins change to 0?  What target AFR is in the table at whatever comes at the next throttle opening? What target AFR is in the first 5% bin with a non-zero target?

DynoJet question: Does 0 in the table mean "ignore" or does it mean a target AFR of 0?

[EEL]

I have posted an image of Ungeheuer's AFR fuel table below. Provided in a different post but its easier to have it visually here



You can see the cruise range established here (with the higher afr's. I'm getting issues at the transition from 0 - 2 to 5 at 4k ish. I'm wondering if this is due to an excessively lean condition at 0 jumping to a much richer value at 2%

The value "0" in the table means ignore. Otherwise it will give you suggestions to modify the fuel table based on the setpoint you indicate in the AFR.

Dynojet says to keep zero's in the 0 throttle an 2% and low rpm range of the autotune. I have attached the youtube video on this. Skip to about 1 min 50 seconds and watch for about a minute.

[Dirty Duc]

PCV isn't very full-featured, is it?

I like ung's table better than the DynoJet suggestion.  If you are running a target table that looks like the DynoJet suggestion, I would expect it to act like your description.  If you are using ung's table or something like it, then I would expect to find the problem somewhere else.

[Speeddog]

What does your throttle % show when it's closed?

[EEL]

Are you indirectly asking if I set the range on the PC-V? If so then yes I did.

My throttle shows 0% when its closed. 100% when its WOT. I had a PC-III on my old bike so familiar with that.

Its the second thing I did. First was to turn the bike on and off 3 times in a row as I was told this resets the TPS on the newer models.

[EEL]

PCV isn't very full-featured, is it?

I like ung's table better than the DynoJet suggestion.  If you are running a target table that looks like the DynoJet suggestion, I would expect it to act like your description.  If you are using ung's table or something like it, then I would expect to find the problem somewhere else.

I am using Ung's table at this time.

[Dirty Duc]

I am using Ung's table at this time.

What does your actual PCV fuel table look like?

How much authority does your autotune have?

[EEL]

I'm not sure what you mean by authority. As mentioned, I have factory 02 sensors removed via Rexxer Flash. Technically the PC-V has full control over the entire fuel range now.

As for the maps themselves, I will have to take a snapshot of the most recent updated map with accepted trim values later today. I've been trying to ride the bike for the last couple of days in various environments (all at approx the same elevation) to ensure I can broaden the mapping range. Currently on the 4th iteration of trim.

Autotune tables aren't showing much change anymore for the already mapped rpm and throttle input locations.

[Dirty Duc]

Definition for this thread: authority = amount of change it is allowed to make at once.

The maps will hopefully tell the story.

[EEL]

20 percent at a time

[Dirty Duc]

20 percent at a time

IMO, that's pretty aggressive with what I believe to be narrow band sensors.

I assumed that part of the reason for the 13:1 target was because of the narrow band range of effectiveness.

Sometimes engines want to be a little richer than that, but a narrow band isn't usefully accurate very far off of stoich.

[EEL]

These are wide band not narrow band