What have you done today with your Austin Seven

[Charles P]

Sliced a block in half, as you do.
Useful to get the exact topography. 
This was a late 30's block that split under duress a few years ago, causing mayhem. 
The bores are +60 so it's instructive to see how much metal is available to go further. Not very much in my book.

   

[Ivor Hawkins]

Those waterways are amongst the cleanest I’ve seen!

[Charles P]

Those waterways are amongst the cleanest I’ve seen!

It surprised me too. I was expecting much worse but the cooling system had been flushed through with hot Fernox DS3 descaler a couple of times, which probably helped

Charles

[Austin in the Shed]

Managed to bore one out to 60 mm once and not porous ran great for about 150 miles then started letting in water,when dismantled the wall had split.It was about 1/2mm thick.

[Hugh Barnes]

Interesting, isn't it. I had a three bearing engine in the Cabriolet that I ran for many thousands of miles which was bored to +.080" and never gave any trouble. Pure chance or a different mould giving thicker cylinder walls?

[Tony Press]

Interesting, isn't it. I had a three bearing engine in the Cabriolet that I ran for many thousands of miles which was bored to +.080" and never gave any trouble. Pure chance or a different mould giving thicker cylinder walls?

I would say pure chance - from what I hear for everyone claiming a successful 80 thou overbore there a number of blocks that give a problem. 

But go ahead  and try - you could be lucky