1855 gas engine manifold question

[KS 640]

I am replacing the intake manifold gaskets on an Oliver 1855 with 310 gasoline waukasha engine.
What is the proper amount or torque for tightening the manifold stud bolts?

 

[Cash4Toys]

25-27 ft lbs. Per the manual.

 

[J. Schwiebert]

Run it about a half hour to warm the engine up and then retorque it. J.