[wilf leek]

Simon - just one more thought. Was the block thoroughly cleaned down after machining? I mean several times, using ATF or similar on rags until every last trace of honing grit is gone?

Get your machine shop to measure those bores at several points down the bore - I wonder if you have tapered cylinders? Boring without deck plates can do this - the cylinders take up a different shape as the heads are torqued down.

Also, I would 'phone the piston supplier tech line to double check their piston/cylinder clearance recommendation. 3 thou sounds a tad light for forged pistons.

Now get this thing fixed - I wanna see you with a smile on your face at Stoneleigh!