if your points are like 193 to something, 230 could be your final score.
Calculation method:
Your final score = minimum + (maximum - minimum)*4/6
Some universities may require a little bit more than 4 in writing section.
Good luck
"If you are not too bad at grammar, I think it's enough for toefl writing to recite three typical articles,which are important and you can choose from New concept 4 or toefl reading comprehension. The articles should meet toefl writing requirements.