Re-lining an S block

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360gts
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Re-lining an S block

Post by 360gts »

I have a thin flange S block that was bored to 74.5mm....has anyone successfully re-lined these bores back to Std.?
The engine shop are worried that the block may crack between bore 2 and 3.
Have to admit...sure looks thin.
My suggestion is to hone the bores and machine the liners down to within a few thousandths rather than try and take more out of the block itself. Then press the liners all the way down into the block and machine off the excess at the bottom for crank/rod clearance....
That would allow the liners to bottom against the block webs....reducing the need to bore the block and leave a step for the liner as is the normal process.
Thought of building a steel support on each side of the block to put support in the middle of the block.
Ideas/comments please.
carbon
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Re: Re-lining an S block

Post by carbon »

I think 74.7mm is quite a bit more than the o/d of standard liners. There are some liners with thicker wall, but again I don't think they are as much as 74.7mm.
360gts
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Re: Re-lining an S block

Post by 360gts »

Hi,
We have all sorts of them over here...we can machine them down to the size first.
Hoping we can save this block.
Cheers and thanks for your input.
ianh1968
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Re: Re-lining an S block

Post by ianh1968 »

I'm very interested in the sizes mentioned here...

The 74.7mm size was the old Triumph piston...
The 74.5mm size - Would this be Simca +0.5mm?

I've just got hold of some Simca pistons recently and the
gudgeon pins are a bit larger (22mm?) but I have plenty of
spare rods that could be modified.

Ian
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