Well here is the response I got from KB about oil for the blower. This is what they use.
"We use a straight 50W full synthetic oil from Redline in our compressors. The problem is no production vehicles use a straight weight oil, modern engines use a multi-weight oil. Unless you have a local race or offroad shop you won't find any in the average parts store. You'd have to order it from us in 8 oz. bottles for $4.50 + shipping or order from and online store or Redline direct."
"We use a straight 50W full synthetic oil from Redline in our compressors. The problem is no production vehicles use a straight weight oil, modern engines use a multi-weight oil. Unless you have a local race or offroad shop you won't find any in the average parts store. You'd have to order it from us in 8 oz. bottles for $4.50 + shipping or order from and online store or Redline direct."