LOL.. For years, even down under here in Australia, people have been sourcing the 400 B blocks for strokers etc...
I think calling it a secret is a little optimistic.
But hey, you got your mug on the wwwintertube right?
Written like another person that didn’t actually watch the video. I was talking about the cold weather block. Not many people know about it. If they have, they may not have actually seen what the mains looked like.