What is the history of the car and the engine? Did you recently acquire this car as it is, or did you build it? Was there always a knock issue or did it just start happening recently?
If your going to go through with the power logger, make sure to get a fuel pressure transducer and a 3 bar MAP sensor if you already don't have one. This will allow you to see/log boost and AFR which will provide far more info than watching gauges while driving. For example, you may have a lean spike, which is really hard to see when watching gauges, but very easy to see when logging. If your not familiar with these things, learning will take some time, but will result in a very good running car and learning a lot about your car along the way.
If your getting knock at 10 psi at a 10-11 AFR, it's probably not a fuel delivery issue from the pump. It could be false knock or knock caused by something else. The 50-60 degree air in the Midwest we have right now is great for these cars, you should not be seeing KR at a 10.6-11.0 AFR. On the street I target 10.5-10.8 AFR to keep it safe.
Who's chip is in the ECU? Have you tried to remove timing from the chip to see if the KR is reduced or goes away? Try this, it's an easy test.
How is your transmission? A weak and or slipping trans can cause false knock.
One poorly flowing (possibly plugged) injector can cause knock because one cylinder could be lean and your wideband is measuring the average AFR across all 6 cylinders. It only takes one lean cylinder to create knock.
How do the plugs look? Do they all appear even in color?
You mentioned UR6 plugs. What are they gapped at? If your on the stock ignition, you may need to gap them much tighter then what they come out of the box.
I have struggled with the stock ignition when pushing boost above 20 psi. I know stock ignition was great back in the day when real OEM parts were available, but now the aftermarket replacement coils and ignition modules for the OEM system seem to be mediocre at best. Finding a quality OEM AC Delco setup is difficult and expensive. I was getting a lot of KR that I couldn't track down and when I switched to a TR6 ignition it went away and the car ran much smoother and picked up top end power. Not saying this is your issue, but something to keep in the back of your mind down the road if you start to push the car harder.
Also, in my opinion, you will reach the limit of the 80 pound injectors and that single 340 pump on E85 way before you reach the potential of that head/cam/turbo combo. The amount of boost you can safely run will be limited until you have the fuel to feed that engine combination..... just something to keep in mind.
Also, here are a few things I have found that have caused me to see KR.
-Slipping trans
-Up/down shifts under heavy throttle can cause some KR.
-Cracked Spark Plug. (this could be real KR)
-A bad plug wire. (this could be real KR)
-Spinning of the rear tires. I see false a little knock when my drag radials get towards the end of their life from the tires spinning and me not realizing they are spinning. A fresh set of tires and that small amour of KR goes away.
As you can see the solution may take some testing to figure out.
