Surging with E-Force

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I'm having trouble troubleshooting the cause of a light throttle surge. I have a surge coming to a stop too- won't die but loses too much RPM then overshoots which may be related, but i haven't tackled that yet. I thought that might be torque tables, but I don?t understand those relationships ? yet. It looks like something is pulling timing, but I don't understand how to determine what to look at next. I've tweaked the torque tables, knock sensors, and only God knows what else; at this point, I'm just chasing my tail.

We're working on a 2012 Avalance with the following setup.

New GM L9H crate engine with stock internals. I'm at 2,000 miles on the new 6.2. Originally I tuned it and was running great NA but some kind of sickness hit me, and I installed an Edelbrock E-Force Stage 1 kit. I've used part of Edelbrock's tune for ( was MAF only) but I've tuned and enabled VVE and MAF.

6.2. L9H stock internals
E-force @ 6lbs
Shorty headers
High flow cats and Borla exhaust
Edlebrock Injectors with their data
2-bar Bosch Edlebrock scaling data.
3.73 gear
I was running 93 Octane with a bottle of octane booster for the attached log.

Thanks.

Avalance Log.hplRunning Tune w-Eforce.hpt

[smokeshow]

The light throttle surge is the cam phasing as the blower makes a transition to boost. A simple fix for that would be removing all of the part-load cam retard and just utilizing the high rpm retard for power. As for the surge while slowing, definitely spark retard requested by the trans. You didn't pull the trans file down with the engine though - nothing is available in that .hpt you posted. When you do get a log file again, be sure to include and and all torque requests and values. Helps narrow it down.

[[email protected]]

The light throttle surge is the cam phasing as the blower makes a transition to boost. A simple fix for that would be removing all of the part-load cam retard and just utilizing the high rpm retard for power. As for the surge while slowing, definitely spark retard requested by the trans. You didn't pull the trans file down with the engine though - nothing is available in that .hpt you posted. When you do get a log file again, be sure to include and and all torque requests and values. Helps narrow it down.

Awesome, thanks for the tips.

[Frost]

.. As for the surge while slowing, definitely spark retard requested by the trans. You didn't pull the trans file down with the engine though - nothing is available in that .hpt you posted. When you do get a log file again, be sure to include and and all torque requests and values. Helps narrow it down.

Yessir this is it... Over in the trans side, under Torque Management ... turn OFF Closed Throttle Torque Management and that timing dip that happens every time it drops a gear when rolling up to a stop will end.

[[email protected]]

Yessir this is it... Over in the trans side, under Torque Management ... turn OFF Closed Throttle Torque Management and that timing dip that happens every time it drops a gear when rolling up to a stop will end.

Thank you, sir. That's great info.