well i was switching flywheels from my na to the turbo motor and i noticed that the na flywheel was stamped with 326. and from my knowledge n326 is s4 na. and the turbo flywheel was stamped with n370 which would be a s5 turbo. so my question is what is stamped on the back of a s4 turbo flywheel the back of a s5 flywheel?

 

There's an N350 somewhere amoung them, but not sure which.

 

ok well change of question, how do i tell whether this is a s4 or s5 motor. anything that will stick out like a sore thumb?