my friend got this turbo, not quite sure if that is s4 or s5 since there is no known one to compare. done some rearch, didn't see an obvious answer. the mark near the DP manifold is "PD289". the mark near the exhaust manifold is "899-1"

thanks

 

The manifold will have diffrent sizes on the exhaust side for an s4

S5's equal.

 

The wastegate's are different.

 

the wastegate on the s5 has two holes, the s4 has one

 

S4 wastegate actuator rods are straight. S5 isn't.