"O" precups

[625fireman]

So I opened up a 6.5 today and found "O" stamped precups...... Maybe I missed something on here but I had never heard of them. So I matched them up to my diamonds and they are quite a bit larger. I am wondering if they are stock that way or did someone open these up??

 

[Mike K3500]

Pics...?? ... of both side by side, would be great.

 

[ak diesel driver]

I may be way off but I thought I read somewhere the military turboed optimisers had big cups in them

 

[WarWagon]

One dot is 1995 turbo precups. What do you mean by "O"?

Out of head are 1995 turbo precups, heads are 6.5 NA and 6.2 Military NA. 6.5 NA is bigger in head one...

 

[625fireman]

Thats them warwagon. I wasnt thinking dot for some reason. That makes sense. I knew it was a later engine but no idea what year excactly.