Endless surly noise to become greater (4)
I believe the answer is:
grow
'become greater' is the definition.
(synonyms)
'endless surly noise' is the wordplay.
I cannot really understand how this works, but
'noise' could be 'row' and 'row' is found in the answer.
A single letter 'g' remains which might be clued in a way I don't see.
This may be the basis of the clue (or it may be nonsense).
'to' acts as a link.
Can you help me to learn more?
(Other definitions for grow that I've seen before include "Become bigger" , "Develop - propagate" , "Multiply" , "Mature" , "Expand" .)