No. You need a torque wrench to set torque. Some people use torque bars to set torque but there's no need for those unless you are on a high volume manufacturing line. Just use a torque wrench. On rare occasions, I will use a lower pressure when I want more control.
The only reason that I mention 90 psi is that almost all the impact wrenches out there are designed to be used with maximum 90 psi.
I have an Ingersoll-Rand unit that is rated for 600 ft-lbs, but I never use it. My cheapie Chinese made impact wrench rated for 450 ft-lbs seems to always work.
However, I would not skimp on the impact socket.