Evening all,
So I took the 3.9 block to our local engine shop today to get it honed to remove the lip from the old rings, but a quick spot of measuring is showing 12thou variance along the depth of most of the cylinders, so beyond the realms of a hone. The price for rebore to +20thou and having the block skimmed is pretty reasonable, and as the rest of the block is good that would seem the way to go.
I'm really just wondering if a straight rebore with oversized 9.35:1 pistons is the best plan or are there any (not hugely expensive) upgrade options I should think about? The C.R. on the V8 seems a bit low to me, I would have thought around 10.5:1 would be well within the knock margins of normal unleaded these days, but I'm not sure if there's any easy way to lift the ratio on a 3.9 without going to exotic forged racing pistons.
Advice appreciated!
Cheers,
AC.
P.S. The engine shop had a Brodie head from an offshore powerboat that had dropped a valve - big block Chevy, around 9 litres, over 1,000hp and blo*dy huge!