Editing DFCO to eliminate decel popping

[Joe6pt0]

On a stock cam LS2 with a cat back only (stock cats) what kind of minimal parameter changes should I look at to help eliminate decel popping?

I'm assuming it’s just easier to turn it off completely if I don't care about fuel economy or larger engine braking-correct?

Also, when the time comes for headers/no cats how will this change?

I would think that since the exhaust isn't flowing quite as freely with only a cat back (as it would with headers/no cats), it shouldn't take too much of a change to see results. Maybe I'm mistaken which is why I'm asking

[Joe6pt0]

Another question I just thought of.

Does anyone add fuel to the low kPA values in the VE table to help out also? Or is that more for a cammed/header engine?

TIA

[shizon]

Joe,

Start playing with ramp in and ramp out rates in the blending tables depending on when you're getting the popping. I would start slowing them down little by little and see what effect it has.

You'll have to let me know how it goes.

[PurplePiss]

Just turn DFCO off. For me, it saves no gas because I drive like an idiot all the time.

[12secSS]

Show us a log of when this happens, it may not be DFCO causing the popping. I have modified the DFCO values quite a bit on different vehicles and have yet to experience this as a cause directly from DFCO.

[jimmyblue]

If you don't cut fuel, and have a higher minimum injector
pulse width than the deceleration airflow can burn, then
post-combustion becomes more likely (popping). Look at
the injector pulse width on decel and its relation to the
dynamic cylinder air value. You would expect a straight
line relation (within closed loop operating ranges) but it
may be you are way above the line, when air goes to
roughly zero.

[Joe6pt0]

Joe,

Start playing with ramp in and ramp out rates in the blending tables depending on when you're getting the popping. I would start slowing them down little by little and see what effect it has.

You'll have to let me know how it goes.

Thanks for the info Shaun, but we don't have any blending tables in the LS2. At least not available yet to us to modify. I did open an LS1 file to see what you are referring to. So you are assuming it is more spark related?

All we have available currently for spark is entry and exit spark vs rpm.

I do just have my DFCO turned off but I still get some minor popping on decel. Its not terrible now but I know when I go headers/off road pipes it will be worse.

[posenheimer]

Id like to see some more information on the DFCO and see some examples... i experimented with it and tried to make it aggressive and over did it and it caused driveability issues out the ass, so I turned it back off til I can obtain more information.

[IDRIVEAG8GT]

Id like to see some more information on the DFCO and see some examples... i experimented with it and tried to make it aggressive and over did it and it caused driveability issues out the ass, so I turned it back off til I can obtain more information.

Dead post revisited lol.

[08RED2500HD]

http://www.hptuners.com/forum/showthread.php?t=36230
This tune of mine has no poping
Feel free to review

[edcmat-l1]

Easiest way is just set the entry and exit spark to something like 15 or so. Will take 90% of the popping out. DFCO will still work, just won't pop.