Calculate $\Delta H^{\circ}$ for the following reaction:

$$2C_8H_{18} + 25O_2 \rightarrow 16CO_2 + 18H_2O\text{.}$$

The values of $\Delta H_f^{\circ}$ for $C_8H_{18}$, $O_2$, $CO_2$ and $H_2O$ are $-269$ kJ/mol, $0$ kJ/mol, $-393.5$ kJ/mol and $-285$ kJ/mol respectively.