jsmotorsport.com
jsmotorsport.com
I don't think the JS pistons will fit the MAP con rods.get 10.5:1 and a thicker head gasket. Or 9.5:1 and thinner. Likely the former is safer.
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JS Motorsport Compression
Copper cylinder head and base gaskets in various thicknesses are now available to adjust compression. Standard thickness is approx .040″. Adding .040″ to a head or base gasket will lower the CR approx…jsmotorsport.com
What about these - nothing in 10:1?
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Complete set of two Norton lightweight Flat top forged pistons 750 to 1007cc. For JSM longer rods.
Norton pistons, Wiseco, JEjsmotorsport.com
Their website says 9:1 with.040 off the head. Wonder if their numbers are with a base gasket?Seems you get 8.5:1 or 10.5:1 compression ratio, nothing in between. My head has been planed and now 8.5 becomes roughly 9 or 10.5 to 11. I was looking for 10:1 Any suggestion on manufactures would be appreciated
Answering my own question:Their website says 9:1 with.040 off the head. Wonder if their numbers are with a base gasket?