Jewels I hadnt noticed any problems with engine it had been running fine been racing and had done a few dyno runs before I pulled it off the road with no problems. I hadnt done any compression checks that would have shown something was wrong.
It is possible that I had assembled it with a slightly bent rod years ago. The only reason I noticed was because both no 2&3 where at the top of the bore. The rods had been race preped with the chev ARP bolts peened and balanced I dont know if they would have picked the bend up then. Its only very slight. Anyway better to find out now then later with a leg out of bed.
Cheers Andrew

Getting water in through inlet .. Or may be a fuel injector leaking badly or ECU malfuction causing the injector to stay open .. I dont think a bent rod would last long before it broke .. from past experience .. any way just a thought .. I have heard from other people that copper head gaskets tend to leak easily .. i had a twincam engine that would only leak water in to the cylinder when it sat for awhile but was ok when running .. there was a crack in the cylinder head from the exhaust seat to the water jacket .. well good lcuk mate ..lucky you found it

andrew wouldve been nice to find out how it happened tho.

we do regular leak down tests now for the peace of mind it gives you that everything is ok in the combustion chamber