I'm using the standard 7mgte computer in my 84 Supra with the 7MGTEU. And have had it running on 14psi.
Or are you talking about the stock 5-ME computer with 7MGTE??? If not... I've hit fuel cut at just over 14psi on not the last dyno Day but the previous. On the road it seems fine . Although I've since recently turned it down to about 10psi due to the clutch slipping.
On another dyno it was on 10psi and the AFR was at 12.1 @ 4900rpm.