Let each of the two ellipses \( E_1 : \frac{x^2}{a^2} + \frac{y^2}{b^2} = 1, (a > b) \) and \( E_2 : \frac{x^2}{A^2} + \frac{y^2}{B^2} = 1, (A < B) \) have eccentricity \( \frac{4}{5} \). Let the lengths of the latus recta of \( E_1 \) and \( E_2 \) be \( l_1 \) and \( l_2 \), respectively, such that \( 2l_1^2 = 9l_2 \). If the distance between the foci of \( E_1 \) is \( 8 \), then the distance between the foci of \( E_2 \) is:
