Undersize cooper s pistons and odd 997 pistons

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251 ENG
1275 Cooper S
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Undersize cooper s pistons and odd 997 pistons

Post by 251 ENG »

Has anyone ever come across any reference to prototype cooper s engine / FJ with a bore size smaller than 2.780" ?

I have a set of NOS BMC pistons , part number 8G 243416 on box and AEG 034110 on piston

They look just like and early factory 4 ring piston but are to suit a bore of 2.750" ??

Also got some 997 pistons , part number 12A 406 , thats a new one on me :? :?
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Simon776
1275 Cooper S
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Re: Undersize cooper s pistons and odd 997 pistons

Post by Simon776 »

8G 243416 are a 1275cc +10 thou Grade 6 piston

12A 406 is (and here's the bad news) a low compression 997 piston - surprised you haven't come across those before.
The power of accurate observation is commonly called cynicism by those who do not possess it.
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