I just got the cylinder heads off the 2.8 and found about 4 of the 6 cylinder walls are scored with scratches deep enough to feel with your nail. Here's a pic of the worse one the others are very minor all of them have scratches at the bottom of the cylinders. What could have caused this on an engine with around 28k? Will I need to go to send it to a machine shop or would a good honing fix this?

 

Broken rings?
I'd have a machine shop look at the bores, maybe they can be machined out.

 

I was thinking it might be broken rings all the piston tops have an oily residue on them and they are all scored. Hmm maybe 3.4 swap time

 

I got a good 3.1 today for free with 6x,xxx miles on it and it was pulled to swap a v8 in. It should do pretty decent with the mtc-5 cam. Not expecting a race car just a smooth daily driver .