If you must do it with the 3 stone springy job then do it lightly, fit the pistons and rings and push each piston 1" down the bore. Fill each bore to the brim with paraffin and see how quickly it leaks down.

Call it what you like. It was a 3 finger tool. But a commercial vehicle one, not a car one.

It took a bit of time. But nothing like the time you suggest. Done in situ with a large electric drill drive, but operated by a man.

Now there's an interesting bit of confusion to add!

I work in Imperial, so I'd cheerfully assumed that the original bore was 2.2" - it had never occurred to me that usually-quoted 56mm isn't an exact conversion.

So, can anyone confirm with absolute authority that a +060" rebore should finish at 2.260"?

Location: Herefordshire, with an "E" not a "T".

2.200" converts to 55.88mm

56mm converts to 2.2045" only 0.0045" ( 41/2 thou.) oversize from standard.

Ian Mc.

Location: Shropshire

I had always understood it to be 2.2 bore. 3 inch stroke.

This works out to be 747.48CC assuming pie to be 3.1415.

If you do it with 56mm and 76mm you get 748.73CC

That seems to confirm the imperial dimensions.

Martin,It seems a lot of interest in your project and although I agree with some of the opinions as to "doing it correctly" I understand your initial request for an economic rebuild option. There is obviously some confusion as to the measurements of both bore and piston diameters and their compatibility,there is really only one definitive answer and that is to get both measures professionally. I just googled Precision engineers in your locality and there would seem to be quite a selection. I'm sure one or two would measure the dimensions for you at a reasonable cost. Camcraft in Bishops Frome may be a good start. Once you have good compression, do you have a crank and rods good enough to take the load? Trouble is when the ball starts rolling nobody can say where it will stop. Best of luck.

Location: Piddle Valley

Thanks Peter.

I think that the excitement caused by bores and pistons is enough for one decade!

The full horror of what I'm doing with crank and conrods will remain a secret between me and my engineer's blue!

Location: Herefordshire, with an "E" not a "T".