Zapperosini the information given is not enough to really help you out. It looks like the SHR you gave was from your outside air condition to your desired room air condition. Not the actual SHR for the load in your space. The desired room condition with that SHR cannot be met with conventional cooling equipment. The way you are approaching your problem you need to determine the SHR for the space load and ignore external conditions except for their possible relationship to conduction and convection of heat into the space through walls, roof, windows, physical openings, etc. The cooling load & associated airflow required to maintain space conditions is a separate problem from the cooling required to get your air source to the required conditions.
For example your space may have a 12,000 BTU load with an SHR of 0.9. If your desired space condition is 75F DB/ 50% RH you would need to leave your coil at approximately 56F DB/55F WB with 400 CFM of air. But if you have to provide that cooling via 400 CFM of air that starts at 94F DB/74% RH air your total load would be 51,480 BTU. You could take those new numbers (94F to 56 F) and calculate an SHR but it doesn't really have any meaning.
