| Is the compression ratio of a SP altered that much when fitted with BP pistons, I only have the Haynes manual for the 748 and it quotes 11.6 to 1 for the SP and 11.5 to 1 for the BP.
If the heads and valves are the same I wouldn't have thought dropping 0.1 on the compression ratio would make much difference.
Simon I should be able to get them over to Dave's no later than Wenesday afternoon although it may be as early as tomorrow if work doesn't phone needing my services and your still happy going with BP ones.
As I said I also have a few other internals so was there anything else required in the bottom end. | 
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