I have received another quote request from one of our customers, being fairly new at the "Peening Game" I have been able to stumble my way threw most jobs with the literature available to me online and in house, however. I am being asked to quote peening to a compression spring with a wire diameter of 1.375" (5160H) I can not seem to find any information that tells me what size shot to use? Or achieve what Almen grade and intensity the customer has no more information other than ASTM 125 at this point I am lost.

Any help would be appreciated

A great deal of useful information is available using the EI Library (enter "springs" in Search box). It is, however, most unusual for the customer to ask the peener to specify peening conditions.

You need to ask a lot of questions:
1. Why do you want to peen? Are there fatigue failures?
2. Where do the failures occur? (inside, outside, hook)
3. When do the failures occur? (number of cycles, stress level)
4. What is the desired load range and life cycle?