What is the max boost you can run on a HT-71 62/14 turbo? I know you can safely run 45 psi on stock head gasket.

 

safely or what the turbo will make?

 

Agreed, there are a lot of different milestones as boost goes up.

For reasonable efficiency, you should keep it around 40 or less.
Going up in boost, you'll enter the HG danger zone around 50-- some hold lots more, some hold less.

Finally, you risk grenading the turbo if it's pushed too far-- but I'm WAGging that would be around 65-70psi with a tough turbo like that HTT.

JH