I think this guy probably measured the displacement incorrectly. And by the way, just having the bore will not tell you the size of the engine. Aside from that, GM never made a 427 small block, well, at least not until the introduction of the LS7 in the lates C6 Z06 Corvette.
Now, I'm sure somebody will/could come up with a theory about how a rogue machinist in GM's engine plant bored out some SB 400's to be 427 cubic inches or something like that, but this would simply be a fun story. In fact, I seriously doubt you can bore a factory GM 400 small block that much without the walls being paper thin.
There are a number of GenI 427 small blocks built these days by guys like Bill Mitchell, Dart, etc., but these are all aftermarket companies that have started doing this within the last, oh, say 10-15 years by casting their own new blocks. But again, my bet is that the guy just doesn't know how to measure displacement.
I will stand corrected if someone has documented proof, but I'm pretty sure that won't be necessary.
Last edited by jknight16; 09-16-2008 at 02:36 PM.