his old tuner got matt from nistune to put on a slightly advanced base tune with bit more fuel and no limiters SAFE as in AFRs wasnt lean its as safe as it would be getting it tuned to 13PSI from a tuner
and the WHOLE setup isnt different its just goin from a gt3071 turbo to something around the same HP rating so im not to sure how it would be UNSAFE and blow something on 13-14psi if most guys turn there boost to that on a UNTUNED ecu