Looked forward to getting the rotating assembly put back together on my 318 rebuild and stumbled upon this. Can't saw with 100% certainty that I didn't cause it but I know i didn't drop this piston. Almost thought about just running it but gut feeling says no. Now I have to figure out where I can buy a single replacement KB piston.

 

Yeah, if you try and run that, you WILL regret it. Contact Keith Black directly, if you can find a number.

 

Make sure you follow the ring installation to the letter. The top of the piston can crack if not done correctly. Not sure if this is all their pistons but worth looking into.
https://www.hughesengines.com/TechAr...ticpistons.php

 

Will do. The instruction sheet it came with stated to run a gap factor of .007 per inch of bore so at 3.93 I gapped them to .0275. The rest of the pistons were ok. That one looks like it got knocked at just the right spot where the metal was at its thinnest for the valve relief. Not sure when or how it happened but its in the past at this point.