im wondering a couple things...
Firstly... you said you have a Lexus AFM upgrade with (what I believe) stock electronics. This is definitely needed if your running with the 560 cc injectors. Are the injectors high or low impedance? Second, I wonder about your 10.2:1 AFR's. Not being an expert in this area, I'm wondering if your still running with a stock ECU installed or on sole standalone and also, where are you pulling your AFR reading from? What gauge/sensor?
Im just going logically and if your running 10.2:1 (and that is indeed what the stock ECU sees) your going to be doing some odd things. Not quite sure how the ECU would handle that because it wants to see a 14.5'ish:1 at cruise and idle. 10.2:1 is nice for acceleration as the ECU tries to prevent problems, but I would assume the AEM would deal with that. So... that makes me wonder how you tuned this puppy....
Again, Im not by any means an expert, but from the parts I think your running, this should be a really bang on setup. The only part I don't understand is the EVO injectors (not familiar with those). If you are indeed running the Innovate AFR, that is supposed to be a very accurate sensor/gauge.
As another small note, I found that while running a similar set up (no cam upgrades though and using 550 injectors), I would overfeed at high revs and had to cut my fuel pressure back to about 26 psi. If I didn't, I would bonewash the cylinders at anything above 4800 RPM as I just had too much fuel flowing (no standalone or piggy back at that point, just the AFPR and 550's running off the ECU with the Lexus AFM upgrade).
All the little uncontrollable's along with the limitations of running this way is what kicked me into doing the standalone/T4 setup. Not being a tuner, I don't know if a bad tune would be able to do this.. but that was my first thought.
remember.. Im just blurting out thoughts... Im not a mechanic... because Im curious how this ends.