im stunned that its no pinging at 14:1 AFR up top end ..
usually can run 14:1 down low before boost kicks in, but then it should be 11.5 to 12:1 ..
first thing if ECU is out of the quetion, rising rate FPR 2:1 rating, to get the injectors flowing that little bit more.. just to get that AFR a bit better....
like $200 and will be alot safer than what your doing now.