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Hi, does anyone have the block drawings in PDF form that they can email me, or at least the height of the block from gearbox mounting face to head mounting face in as new form, just checking the accuracy of the original machining which as Keith Calver says on his FB page, can be a few thou out from end to end.
The block is an original gold seal recon so it needs new liners fitting properly as BMC didn't.

If it's any use to you I have a standard 1275 block here, on a surface table and a digital height gauge it comes up with 8.8886" at the front and 8.8901" at the rear, so a difference of 0.0015". If you turn the block over with the head face down and measure from the main bearing centreline it's spot on.
You can check if the block has been skimmed by checking if the original piston codes are still visible.

The BMC engineering drawing for the Cooper S block shows 8.881-8.891”

Thanks, I can get an idea of what state the block is in now, the liners need replacing as they moved & caused a few head gasket issues in 1981.
I didn't line bore the mains as it was a Gold Seal block with a good STD dia bore surface, the crank turned perfectly then, when I stripped it recently the main bearing shells were unmarked, the big end shells were slightly marked as I took the centre pick up pipe out as the filter kept getting blocked with debris.

ps we didn't measure much in 1981, we left it to machine shops,
nowadays we measure just about everything after purchasing a huge amount of measuring equipment & record my findings on a build sheet, with my day job we have lots of drawings of the parts we assemble.
So a block drawing would still be useful

winabbey wrote: ↑Fri Jul 12, 2024 1:44 am The BMC engineering drawing for the Cooper S block shows 8.881-8.891”

Does this drawing show the distance between bore centres?
The distance between 2 & 3, or alternatively 1 & 4.
I am trying to check if my block has been offset bored.
It is at 73mm, and I may need to go to the nex stage (73.5)

indigo wrote: ↑Mon Jul 15, 2024 12:45 am

winabbey wrote: ↑Fri Jul 12, 2024 1:44 am The BMC engineering drawing for the Cooper S block shows 8.881-8.891”

Does this drawing show the distance between bore centres?
The distance between 2 & 3, or alternatively 1 & 4.
I am trying to check if my block has been offset bored.
It is at 73mm, and I may need to go to the nex stage (73.5)

That drawing doesn't show the distance between bore centres but another for the 1071cc engine shows a distance of 3” between cylinders 2 and 3, and 3.0312 between 1 and 2, and 3 and 4.
Did the 1071 use the same block as the 1275?