Best speak to harvey at scs, i had a chat too him a while back about alloy blocks, definetly the way forward. The liners are only £100 each too if they ever need replacing, he has a few past 800hp and one at a 1000hp with no problems so far. im considering getting one as i want 700hp, it works out around £1400 to have a block nikasil linered and the same again if they need replacing so it makes sense long term, plus the cost of a 200 block on top, im sure he said 2.7 cc is a possiblilty as you can order them with a taller deck height too.