Tie up an order for speedy production (4,4)
I believe the answer is:
make fast
'tie up' is the definition.
(thesaurus)
'an order for speedy production' is the wordplay.
I cannot really understand how this works, but
'an' could be 'a' and 'a' is found in the answer.
'speedy' could be 'fast' (similar in meaning) and 'fast' is located in the answer.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for make fast that I've seen before include "Moor" , "put booster in engine" .)