I was meditating and my heart turned to a scripture where the Lord was cutting His work off in righteousness. Not being one to remember scripture and verse I turned to Logos seeking to find this verse of scripture and I encountered marked difficulty. Knowing I cut my teeth on the KJV I was finally able to find that the scripture was Ro 9.28.
I was surprised to find that the Greek texts for this scripture don't match the Bible versions I commonly use. I was able to determine the texts that the modern translations are based on, but when I sought to find the Greek text the KJV is based on I could not find it because there is no introduction or preface to this version in Logos. When I turned to my hard copy there I found no answer either.
So, I turn to all of you. What Greek text/texts is/are the KJV using because it is quite different from the modern texts? And instruct me in finding this information for myself.
KJV:

HCSB:

The textual base for the New Testament [NT] is the Nestle-Aland Novum Testamentum Graece, 27th edition, and the United Bible Societies’ Greek New Testament, 4th corrected edition.
The Holy Bible: Holman Christian standard version. (2009). Nashville: Holman Bible Publishers.