Contribute to good stroke perhaps (4,2)
I believe the answer is:
chip in
'contribute to' is the definition.
(thesaurus)
'good stroke perhaps' is the wordplay.
I cannot quite understand how this works, but
'good' could be 'pi' (old-fashioned term for pious) and 'pi' is present in the answer.
The remaining letters 'chin' is a valid word which might be clued in a way I don't see.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for chip in that I've seen before include "Pay part of the cost of something" , "Club together" , "I pinch (anag)" , "add to the kitty" , "pipe up" .)