TOEFL is completely a piece of joke compared to GMAT
I score 107 on ibt TOEFL with 27/30 on reading
but end up with verbal only 13 on 1st attempt in gmat
and 16 on 2nd attempt.
Don't worry about it.
3-4 days preparation would be more than enough
i don't think 3-4 days will be enough to become familiar with TOEFL.
TOEFL consists of four parts: Reading, Listening, Speaking, Writing.
to get a good score you need to practice, take some diag tests.