Darin Przybilla

Hey fellas, first time poster here aside from the classifieds but have gotten a LOT of info from y'all. I've always been a Ford kid and built more SBF than I care to admit, but I decided to build a 5.3 with twins and stuff it into an '81 Crown Vic. Bought a 2000 LM7 from a dude on CL back in July, supposedly had 156k on the clock and came from a rolled over truck. Paid $500 with all accessories, harness, PCM, and a rolling cradle. Anyway it rained when I was hauling it home, so right away I pulled the plugs and tipped it over, shook it around, blew out the ports and jugs, etc to assure it was dry then squirted some JB80 in each hole and cycled the crank (plugs finger tight). Rolled it back in the corner and forgot about it until yesterday. Had all my parts laying around and the intent was to pull the heads for new gaskets and studs, and check the cylinders. Upon pulling the driver side head, there was a small amount of rusty yuck on the bottom side of cylinder 1 and 5 but it turned freely, so I figured I'd just wipe it out and move on. Nope. There's some pitting. Pulled the pistons, fired up the hone with 320 stones to clean the burrs off, and I can't get the damn thing clean. It actually feels like a protrusion more than a pit, but I don't want to take off too much material. I was getting to the point of just mashing it back together to see how long it took to break a land, but in the midst of this I check ring gap. These cylinders had such a minimal ridge on top before I started honing, that I couldn't catch it with a fingernail and the factory crosshatching was visible. Top ring from piston #1 had a .046 gap in #1 hole!! Same ring has .045 in hole #5 which I had done nothing to yet. Anyway I took all 4 top rings from that side and they read .043-.046 between each hole and only 1&5 have been honed. What the fack?? It was quite apparent that the engine had never been apart (I think), did the factory way overgap the rings? Overbore the jugs? Mic says 3.783 on #1 and 5, 3.782 on 3&7. What's going on here?

JoeNova

They're so cheap, you could probably pick up another short block for next to nothing.

Or you can have that one overbored and drop in some stock LS1 pistons.