Is there a way to find out if an engine is a Zenki or Kouki from the serial numbers on the engine?

 

There's visual differences. I'm not sure on a lot of them, but the S5 doesn't have an EGR valve. You could find this info by searching.

 

The easiest way to tell the difference visually is to look at the rotor housings above the trailing spark plug. The Kouki engine has a threaded bung for the knock sensor just above the trailing spark plug. The Zenki engine has a smooth casting above the trailing plug hole.

 

most that i've run across are Zenki. pretty easy to spot.

 

My post wasn't super useful, but damn... this one takes the cake.

 

most of them that ive run across have spark plug holes

 

I have a friend in Japan thats looking be he knows nothing about cars so I can't ask him to look for a specific part cause he wouldn't know what to look for and he doesn't speak Japanese so he can't ask. I've read somewhere that Zenki's have a two bolt flange on the thermostat housing and Kouki have three bolt flanges. Can anyone confirm this?

 

http://www.rotaryresurrection.com/2n..._s5_diffs.html