[tubman]

I used five foil balls, one in center and four equally spaced around the outside of the piston, about 1/2" from the edge. All were within a couple of thousandths (plus or minus) of each other for each cylinder. It looks to me like Edmunds did a pretty good job of conforming their combustion chamber to the piston top, so I figure it's good to go. The measurements given are for the center of the piston front to back on each side. I am trying to keep anything I do to this setup to be minimally invasive, since all the components are used. I'd rather give up the last 5% gain if I don't have to start grinding on the heads. The head gaskets on the engine, though compressed to .055, look to be in excellent shape, and in a pinch look like they could be reused. It appears no sealer of any kind was used in the initial assembly, as the heads, and then the gaskets, lifted right off the block with no transference of material. I am going to install my new Fel-Pro composite gaskets the same way and hope for the best. It also appears that the factory applied sealer to the threads on the short head bolts only. I was careful and used thread chasers instead of taps and dies to clean the threads. I was able to turn the chasers by hand on the great majority of the bolts and holes. Since this will be the second assembly of this engine, I am planning on using thread sealer on all of the head bolts.

i'l say it again; it seems like I got incredibly lucky with this engine. It had to happen to somebody after all the disappointments we all have had over the years; I'm just glad it was me.