Originally Posted by Gimpinator
Actually that's an FE Series engine - most likely a 428 between the fenders of what looks to be a Shelby GT 500 Mustang.
The GT-40 engine up top has a reproduction Shelby block. You can tell because the Shelby blocks have two side bolts per cap, where original Ford 427 blocks only have one.
Yeah I know... Call me the Klay of Ford engines. I'm a detail Nazi - Eeet must be correckt!
My take on the double crossbolts is that the block is aluminum and needs the extra support because the skirt isn't as strong as cast iron.
At the time that Ford was competing with these engines, I was working for the company in a research area. I saw the 3 valve heads that would have gone to LeMans if the French hadn't changed the rules to prohibit the big engines. The flow lab boss said they were flowing 550 CFM per cylinder.