I'll leave my previous post/edits for historical purposes, but given this comment
Also, I'd like to try solve it myself as much as possible with your help, not you solving it FOR me, pretty much.
I guess I won't continue trying to make progress on the format. Though I do have some additional ideas based on my previous observations.
So to directly ...
22 bytes: a simple guess, if each block contained a float value
double precision X.XXXXXXXXXXXXXXXe + XXX (len 22 bytes).
Maybe this is a bit too simple, so can you give us some examples of your 22 bytes blocks?
Just a comment after read the interesting answer from Bill B:
There is no value > 0x7f
which is unlikely for floats 8.77 I guess.