I am overhauling an 13B Turbo II engine but ,I dont know with year it is,are there differences
When it's finisht the engine is for my 1 gen ,12A car.
thanks

 

Quoted directly from the FAQ:

How do I tell the difference between an S4 and S5 engine?
See the following topics:
https://www.rx7club.com/forum/showthread.php?t=530583
https://www.rx7club.com/forum/showthread.php?t=263870
Lots of Info: https://www.rx7club.com/forum/showthread.php?t=373451
Pictures: https://www.rx7club.com/forum/showthread.php?t=341891
https://www.rx7club.com/forum/showthread.php?t=330057
Good thread: https://www.rx7club.com/forum/showthread.php?t=594874

 

this has never been discussed

 

Yeah well.
the water pumps are different.
S4 housing come with like some kind of writing on it.
I believe s5 fans are 10 blades.
s5 injectors are round and s4 are square.
s5 omp pump is electric not mechanical.
s5 rear side housing has a thicker dowel pin area right next to the oil filter pedistal. S4 is thinner.
s5 Turbo manifold has to separate chambers and the s4 has one big chamber.
The ignition timing on the housings are different.

Now if there is anything I missed please tell me. If there is something wrong please tell me.

 

thanks, i' going to check it