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They're both at low rpm under a fair bit of load, probably real knock but the knock retard is more than needed and takes too long to decay. You could try doubling the KR decay rate and halving the...

I have found the same thing, the knock sensors just suck at picking up high rpm knock. I don't have much faith in them. They seem to work ok at lower rpm. What I don't get is how the early US LS1s...

Your spare maf might be bad too, new ones aren't expensive from Rock Auto or similar. K&N filters can bugger them, especially if over-oiled. At sea level, 20-30 deg C temps you should see cylinder...

Yeah that will do it, if you descreen the maf you need to recalibrate it with a wideband. Should be more like 0.75 g/cyl at peak torque with a good maf.

Low fuel pressure or a bad/dirty maf are the usual causes of this. Hard to say in your case because the cylinder airmass (maf derived) look a bit low but not obviously wrong, and the fuel trims...

It doesn't sound quite like the real thing but would probably fool a lot of people. Did you just crank up the idle spark over/underspeed? I might play with this on my car for a laugh.

MAFs are also different if you're still using it. Timing tables, VE table, trans stuff, power enrichment settings, that's the main stuff that needs changing. I'd leave the VZ knock settings...

You're likely seeing the effects of the IAT sensor heatsoaking, making it run leaner. Oil temp does not affect engine VE significantly.

Heatsoak of fuel in the rails can have an effect too, but...

I can't see fuel trims in your log, but I bet they are way high. It is going into PE mode, but the commanded and actual AFR are way off. The cylinder airmass looks really low so I think the maf is...

30-32 degrees at WOT is a LOT of timing to be running an an LS1, so you may well be getting real knock. Cammed cars do like more timing than stockers, but I would try bringing it back to 26-28 (try...

Post the log and tune too, I'm curious to see what's wrong with it. A jacked up VE table might be pushing it into the burst knock thresholds.

You could save yourself a lot of trouble by just leaving the maf on. Mafless is no benifit on a stock Gen4 engine, no gain in economy, no significant power increase, no improvement in throttle...

The 85mm ones work great - copy paste the table from an LS2 GTO, 2004 LS1 corvette, or any other car that comes with one and it should be very close.

1. Open trash can.
2. Place Granatelli MAF inside.
3. Crush down then close lid.
4. Fit a good stock MAF.

Or you can just leave it off and run SD, but the VE table will need some work, and...

The LTFT of +25 mean the trims are compensating for a lean condition which needs fixing. Looks to be a bad MAF because the airflow numbers are low. It's maxing out at about 210 g/s MAF flow -...

If you're maxing out the stock injectors on a stock LS1 you have low fuel pressure. Pressure will be sagging under load. 126% VE just doesn't happen on a stocker unfortunatly!

It's fine to...

Put the maf and VE tables back to stock. To be blunt... they are completely jacked up! It's not reading lean on the wideband because the trims are brining it back to stoich (just).

Your maf...

I get knock in that 1500-2000 rpm area every now and then too in the higher gears. Pulled a couple of degrees out (I run a bit less timing down there than you look to be) and it's mostly gone but...

I can tell from your narrowbands you're running 14-15 AFR at WOT, way too lean (they're switching at WOT). Fuel trims are jumping around more than I like to see too. Either your maf is...

What are your g/cyl readings at WOT? This will help identify if it's a fuel issue or bad MAF. My fuel trims are spot on and I usually see 0.72 g/cyl at 5000 rpm, dropping to 0.66 at 6000 rpm. ...

O2 B1S1 looks to be working but looks like it's connected to the wrong bank, B2S1 looks to be dead. Or they might just both be dead - that's a really weird log. I can't see anything obviously wrong...