Well Clint
As I read Soltan/Davilla (page 164) they say the R.4 could have either the Renault 12Db or the Hispano-Suiza
8A engines.
Then French officialdom confused the matter with SFA calling the latter version R.19, while everyone else still called
them R.4
I simplify it by just calling the lot R.4....
Happy New Year to you too!
Cheers
Stig