moka-only

Hey
I know this has probably been asked..and I have searched through the forum as much I could...
I just have a basic question..but maybe the asnwer might not be so basic.
How can you tell from an S4 turbo motor to as S5 turbo motor..or vice versa.
I just got a j-spec T2...but I have no idea what series it is..or year its from..kind of sad..but I am in a real desperate situation. Thanks alot for your help guys...I appreciate it. I will let you know ohw the swap is doing

Already been done..
-Taken mainlines from excisting motor (86 base GX N/A)
- Taken turbo off j-spec and begun to clean.
- Taken bell housing off and ordering new clutch assembly (I have to know what series it is so I cant order the right year of clutch assembly, either way will be purchasing, Stage One aftermarket, from dealership.

I will post pics up later on..
Again thanks for advice/help...

Nick

FastA$$Rx7

usually i check to see if it has a electric oil metering pump or not, if it does then its a 89-91 S5 , also there is a differance in diameter on the turbo ( where the intake duct goes ) i think s5 is bigger than s4 but i dont know the dimensions , hope i was some help sorry if i wasnt