Ford flathead
 

I purchase a canadian ford engine flathead 24 stud water neck center crabe style
On the head c7ra-a what the model and year?
I have also a 59ab

C7Ra is later head (suit the C59a, C69a etc. block- 45 to 48) In 1942 Ford shifted the valve line up in the block. This required the earlier heads to be ground out to fit these later blocks.
Those heads came in Cast iron and Ali. The Ali heads give the higher comp. ratio of the two. Both are good with regards the C.R.

Aha! So that explains why I had to have slight amount shaved from my heads, immediately above where the valves lift. Without doing that, the valves would/could have struck the edges of the underside of the relief in the head. Knew there must have been a reason why that became an issue. The French blocks must have been 42 or later in valve design?

Ford flathead
 

For ford engine flathead center neck one or two thermostat ?

One in each head.

The Ford flathead is in fact two separate cooling systems sharing the same radiator.

Hi Tony. Ford actually supplied a service tool (jig) that was used to grind out the valve relief in the older heads to fit the later engines. You flipped it over to grind out the other valve relief in each chamber.
Just to add to Robs bit about the separate engines. One side always runs slightly hotter than the other side. That's normal apparently. The C.R. is not exactly the same, one side to the other. There are other things as well.
Henry Ford's original concept for the F.H. V8 was originally two Model A's, sharing the same crankshaft.

I'm hugely relieved to hear that info, Lyn. It had been troubling me since the heads were modified. I couldn't find anything that told me why they wouldn't work without messing with em.

I took the heads to local engine rebuild place and they did the hard work. We used a head gasket as the pattern where to grind the chambers back to. Figured it was probably a strange quirk with the French flathead blocks. Guess it was a quirk with dear ole Henry instead. He must be up there laughing at all the confusion he's caused!