ASTM A148 does not restrict the manufacturing process enough for anyone to be able to provide a curve. All A148 does is restrict the amount of P and S. All other chemistry and heat treatment requirements are left up the agreement between the customer and manufacturer.
Grade 90/60 for example can be made using a number of different materials. We have made it with 1045, 1520, 1524, 8620, 8625, 8630 and even a 4140 depending on the customers requirements. If no impact are required we would use 1524 in the normalize state. This will not provide great impact properties. If impacts are required we would use the 8620 or 8625 and quench and temper the parts.
Even on the high end with 130-115 there are a number of common cast materials you can use. 4130, 8633, or 4320 would all be good choices but will yield different impact properties.
What are you trying to do with the information?
Bob