I don't remember ever seeing 117, but I have seen 108 in my 124 car and it did a pretty good job. Do you do short hops? If so, then most any cars a/c will struggle in such an ambient temp.

If you're ready to lay down some serious cash and effort, the one thing that you could do to improve performance would be to adapt a parallel flow condensor. Also, you did not indicate that these are converted systems, but if they are, you need to go back to R12 for your situation.