10 Camaro SS Cam Surge, LTFT difference

Hello, I have a 2010 Camaro that has a tsp cam and was already tuned. I installed a gpi ported intake and had my busted mufflers replaced with some muffler delete pipes ( I hate it way too loud). I've been working on the cam surge, got it down more than it was. But right now I'm concerned about my LTFT, B1 is reading +5% and B2 is reading -2%. Car is on MAF only already did one log and added ~4-5% through the part throttle low rpm. I havent put the wideband yet to get actual reading was just trying to get the part throttle fuel trims dialed in closed. Is it possible that there is a vacuum leak on the manifold? Every once in awhile I think the idle problems are fixed then it start to oscillate on coastdown once stopped it goes away and back to perfect idle.
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Possible exhaust leak?

I don't believe so I noticed while I had a big hole in my B1 muffler the trims were off a little so I didn't worry about it now everything is fixed I'm little more concerned.

Swap your O2s and see if trims offset follows, obviously reset trims before scanner test. If it does likely sensor issue, if problem remains id start with a smoke test, plug check and pin testing.

Alright well I swapped my O2s logged it again same problem. Took my wideband and just shoved it down the tail pipe of each bank just to see what it was saying B1 was reading 1.2 lambda and B2 was reading 1.4 lambda. Also pulled B1 plugs just to check it out and they all look good. I'm pretty sure that they are the original Acdelco 41-110. Should I swap the plugs if so which ones yall recommend. How do I get my aem wideband to read on the scanner?
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I also noticed on the last drive B1 trims when upwards and little higher than 20% off throttle.

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Originally Posted by oleblue07

Hello, I have a 2010 Camaro that has a tsp cam and was already tuned. I installed a gpi ported intake and had my busted mufflers replaced with some muffler delete pipes ( I hate it way too loud). I've been working on the cam surge, got it down more than it was. But right now I'm concerned about my LTFT, B1 is reading +5% and B2 is reading -2%. Car is on MAF only already did one log and added ~4-5% through the part throttle low rpm. I havent put the wideband yet to get actual reading was just trying to get the part throttle fuel trims dialed in closed. Is it possible that there is a vacuum leak on the manifold? Every once in awhile I think the idle problems are fixed then it start to oscillate on coastdown once stopped it goes away and back to perfect idle.
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Its normal for the fuel trims to differ a little and the range you mention is completely normal. You likely would have a better driving car if you tuned it in SD only. The MAF will get tricked by the reversion in the cam.

If it normal am I 5% lean or 2% percent rich via fuel trim? They get better than 10% difference at times. How do i get my aem wideband to log on my mpvi2?

Doesn't look all that bad. Few things...

Idle adaptive spark is too aggressive, both under and overspeed. Start with stock values and work them down...bigger cams are sensitive to large spark deltas, so +/- 10 everywhere isn't helping. In gear and

Bit too aggressive on the throttle follower in gear. That's the direction you need to go in, more TF torque, but not that extreme.

Throttle follower step up/down values should be reduced, probably by about half. Gentle changes with a big camshaft.

Coastdown proportional idle for idle overspeed is far too aggressive. That needs to be reduced...its causing the throttle to snap shut as RPM goes over target. Start with stock values, and reduce the airflow reduction if necessary.

Set max idle speed setpoint back to stock value, around 1350rpm. When your idle oscillation causes it to go over the current 1100rpm value, it exits idle mode and contributes to the oscillation.

I'd also reduce the closed loop proportional base by probably half, as it tends to smooth out the fueling and helps steady trims for data collection...but you can take or leave that for now. Start with those other items to calm it down and get some better data on the fueling issue.

So I ended up with this idle its a little better. Now I have a problem where when I'm trying to let off the clutch starting from a stop torque management kick is and pulls 7-20 deg of spark causing the car to fall on its face and jerk. I look stupid when i drive the car pretty sure everybody thinks idk how to drive. also the TM is there when there is cam surge. Idk if its the TM thats causing the jerking but its pulling spark when the jerking is happening.
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Too much idle adaptive spark....cut it in half.