Knocking Issue...

[spirospz]

my buddy has the K-Pro, so we loaded the tune for the 440CC injectors @ 5 PSI. Well, let me rewind here. First, he got the K-Pro back from Hondata Thursday, so he had a few days to tinker before I installed the blower. Right from the beginning, the car was pinging. Stock tune. Tuned tune. CAI tune. Okay, he's low on gas, we'll try a different gas station, make sure it's full of 93 octane, yada yada yada. Still pinging. More pinging on high load, low RPM, which appears to be semi-normal. BUT, he drove 25 miles home, and the thing pinged 1400 times. Now, I have some experience with tuning LT1 Chevy motors, and our knock count is different then y'alls. Because we see 800 knocks on startup alone. So, this wasn't a big deal to me. But, we come on here, and y'all are freaking out about 150 knocks, so now him and I are both worried. It shouldn't be pinging hardly at all on a stock tune, right? It was MUCH better with the CAI tune then any of the three, which seems weird to me. My other thought is that we are on 93 Octane, and I would assume the tunes from JR would be for 91 octane, since that is what it is in most of the US, and even more conservative because their 91 Octane in Cali is oxygenated, or whatever. Okay, we pull 4 degrees, as we read here, and still knock. Okay, forget it, let's pull 10 degrees total. Problem gets better, but is still there, so false knock? The reason we don't think it's false knock is because under WOT, it doesn't ping but like twice. In theory (at least on an LT1), it should be running more rich WOT, since it isn't looking at the O2s, yada yada yada, so is it false knock down low, or real knock? Why does it go away with real throttle in gears 3+, but in gears 1 and 2 it knocks like crazy below VTEC.

We've pulled timing. We've increased fuel. The Short Trim is usually about +-7%, and when it goes into open loop it changes to the 12.5ish A/F command, and stays there. So, the 02's aren't saying it's lean, so adding more fuel won't help, so we retard the timing, and problem is still there.

Now, some history on the car. First, he blew the motor up like 15K miles ago. Beats the hell outta the thing. So, the dealership rebuilt it. We aren't sure what they did, so we were thinking okay, maybe they milled the head a little bit, and that's causing the problem. Even with 10* pulled, I don't think so. Another thing is the car is running some 19 inch Axis Neos or something. So, the wheels are a little heavier, adding load to the drivetrain. And he has a stereo in the trunk, 2 10's. But, I can't see this forcing him to have to pull 10* of timing just to get anywhere with the pinging issue.

Could the dealer have screwed up the knock sensor install? I know the LT1 sensors are very finicky about being properly torqued. Or do you think we have a real issue here? I can try and get him to send me some datalogs if that will help y'all.

And I'm definitely not a pro tuner, nor anywhere near it. So, it might be some user error here.