Originally Posted by gs1973
Dont forget that some XC's had the smaller diameter shafts too and they were not called Black blocks....
The only reason they are called black blocks is because they were painted black in XD/XE falcons...
Id check date codes on the block or the dissy hole if you're chasing a late cast block.
Im not sure why all the fuss is about black painted blocks... Aussie cast square blocks (73-83) are all the same except for the dissy hole, regardless of which color they were painted.
Some later cast blocks seem to be thicker in the bores but ive seen early cast blocks that are thicker too, its random and you'd have to check regardless.