LS7 possible valve float or tune

Attachment 144299
Would someone please look at my log file at time 6:55.844 and look where the MAP starts to drop first at around 6600 rpm and then the MAF starts dropping. Throttle position still shows WOT. MAF shows 9101hz at that moment and I know my MAF tops out on my scale at 9200hz. I've never experienced this before. Car sounded great and pulled strong. I didn't hear or feel any thing that made me think a loss of valve control during pull. But I also know these engines are notorious for valve control issues. I definitely don't want to grenade it. Any help would be appreciated. Thanks

To me, it looks like Injector PW dropped first then throttle. May want to post the tune so some of the more experienced guys can help.

It looks to me like polling had a large interval (~0.5s) then the scanner interpolated with a straight line. At first I thought maybe it's because you were logging too many channels. Then I noticed I could scroll way down in the channel list and see another huge group of channels and was like wtf. Clean that stuff up.

Valve float would show up as stalling rpm as well as high MAP while MAF decreases.

Good lawd get rid of 90% of those pids. Then retest.

Please post complete mod list also so we know what we're looking at. Not sure why everyone wants us to guess at stuff.

Bonus points if you have a dyno graph.

I took your advice and got rid of a bunch of pids and scanned it again on a pretty long drive with several WOT pulls and everything looks great now. My MAF is still maxing out at around 6200 rpm 9200hz other than that it's very good. No weird readings or anything. Thanks again for every ones help

And hopefully a dyno run soon...

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Originally Posted by Blitz4

Attachment 144299
Would someone please look at my log file at time 6:55.844 and look where the MAP starts to drop first at around 6600 rpm and then the MAF starts dropping. Throttle position still shows WOT. MAF shows 9101hz at that moment and I know my MAF tops out on my scale at 9200hz. I've never experienced this before. Car sounded great and pulled strong. I didn't hear or feel any thing that made me think a loss of valve control during pull. But I also know these engines are notorious for valve control issues. I definitely don't want to grenade it. Any help would be appreciated. Thanks

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This looks like the polling rate was too slow. Likely cause too many things are being logged. Also happens with stand alone datalogging.

This looks too lean at wide open.