That simply meant Ford added 5% more nickle into the metallurgical formula for the cast iron to strengthen it.
It was not something they liked to do because it made the block harder to machine.
I had one of those blocks as my first Cleveland build up in 1974 or 5 and when I went to pick it up from the shop the guy got all pissy and said don't ever come back here again with your "crap".
That is some sort of special block and I had to resharpen the boring tool several times for each cylinder.
He then pointed to all of the x's and y's in the lifter valley.
He was wrong about those since all the C's have them but who know's on the hardness of the block.
The Australian's claim they cast the block with more nickle? Who am I to disagree?
Sounds like I stumbled across one? Came out of a wrecked race Pantera too.
[QUOTE]
That's not entirely true. The block that is in my '71 Pantera (I built it in 2000) has NO Xs or Ys cast into the lifter valley at all. It did NOT come from a Pantera.Years ago I had a close friend who's Father drag raced a Cleveland powered Mustang. He was best friends with his engine builder and he told me that when he bores a Cleveland block with the X's and Y's you can actually hear the difference in tone from when he bores one without the X's and Y's. He attributed it to the higher nickel content in the casting.
Ron