Don Terrill’s Speed-Talk

Hello friends

I just need some info about how to ID a hi-nickel 400ci factory block.

I've been reading different advises, so I'm confused.

There's a code or sign in the block to look for?

Hope the knowledgeable members here can shed some light

Thanks in advance!

From what I have seen the 509 block has the rectangle bars cast in the valley meaning higher nickel content in the casting.
The blocks I have machined have had a shinier finished machined appearance and were slightly harder to hone.

There may me others with more nickel but a basic rule to go by is the 400 blocks had way more nickel to make them stronger because of there design.

under the timing cover will be casting numbers cast in the block,
like 010 or 020 or both.

Great info friends!

My 400ci #509 two bolt block have the rectangles in the lifter valley and "010" on the timing cover area.

Guess I'm lucky !!!