I'm rebuilding mine right now. I've rebuilt quite a few motors in my life, former line mechanic for Ford and Chrysler. I figured like you, whats the big deal, how different could it be?
Well it HAS been an education! One of the problems is because the motors ARE so old, which means theres a good chance nothing is "stock" anymore! My block was bored .017, which I thought was odd, .020-30 some even number would be "normal". But NO, not for an FE, seems that .003 increments are "normal" (how bizzare is that,
). Due to the thin wall construction of the block cylinders.
There are a great variety of "parts" that interchange with the FE blocks, just identifying YOUR specific pieces can be a struggle. I'm using a 428 externally balanced crank, as opposed to the internally balanced 427 crank. Mine is a 1U (I had to research that to figure out WHAT it meant).
When I measured the piston pin hieght (compression hieght) it was NOT at all what I expected, the block had been "decked". And the push rods were "odd", real SHORT from "standard" length (under 9"). That even had George scratching his head (Gessford machine) and he KNOWS side oilers! Come to find out my rocker stands had been milled to allow for (guessing here):
1. Clearance for the valve covers?
2. Short push rods mean less valve train "harmonics" problems?
Some interesting "extra" machine work done internally to the block, chamfered
oil holes and such. The motor clearances were on the "loose" side for most everything. My theory? Whoever built the motor last knew what he was doing, and built it "loose" for more horse power (667 horse to be exact).
It's going back together with custom pistons (down to 9.8 to 1 c.r. from 12.5 to 1) and a much milder cam. Tighter clearances too, built to "last" and for the "street". This is the "trickest" motor I've ever built, you can't take ANYTHING for granted with these old motors, this aint no "off the shelf" 302!
I thought this was funny:
When I first took the block into the machine shop to have it cleaned and "double check" the measurements I had all ready taken myself they called and said, "Your block is .017 overbore, we should bore it to a standard .020, OK?" Ha ha, I told them .017 WAS standard, they were like "no way", but it IS "standard".