Piston stamped 50

[nj1639]

Doing some mix and match engine parts swapping. I've a 447 that was supposedly rebuilt but never ran for any length of time, and when it was started it was making some funny noises according to the PO.
I'm swapping the jugs out and noticed that the pistons are stamped with a 50 in the top center. Would this be a half over bore designation?

 

[deadchef]

i believe that would be .50mm or a second overbore. they go in .25mm increments.

 

[nj1639]

Thanks!
Suffering from CRS, its been 6 years since I did my 2 over.

 

[deadchef]

i'm working on a 2 over rephase right now. just got the case together and noticed my cam chain still sitting on the bench. luckily i was able to get it on there without splitting the case again.