I've tried googling for "Time dilation due to acceleration" but found nothing particular. Here when I entered title of the question the site have not shown same question asked already. Upon typing in the question the site found:
Gravitational Time Dilation vs Acceleration Time Dilation
Time dilation in a gravitational field and the equivalence principle
I've read those still do not see clear answer to my question(s) below.
In wikipedia for time dilation there are dilation due to relative speed and gravitational one. However as far as I've understood General relativity is based on "Einstein equivalence principle". And from the principle it follows that acceleration with 1g on a spaceship will be experienced same as gravitation on Earth surface. But what about time dilation on a ship accelerating 1g? (speed still small or accounted for separately if that is possible ...). If time dilation is the same due to equivalence, why then clock in the core of Earth will go even slower than surface whereas acceleration due to gravity = 0 in the core.