That is interesting to note, the last coated engine i had on the dyno was a vg30dett with similar mods to yours except the jwt 700 turbos instead of the 2530's It did not like any more than about 16 deg @20psi with no water/meth (on pump gas) mind you i do use a dyna-pac so it might be loading the engine a bit more than an inertia dyno. with the water on it would run clean at 22-23 deg advance with 20 psi and just over 500 at the wheels. Did not go any higher on the boost as the plug gaps needed to be reduced and we ran out of time.. Will put it back on the dyno again in the spring and see how it responds to some more boost. Your high boost run was that on pump gas ? were you using water/meth?