The V8 Owners Forum -

Ive had a quick google for it but I cant see the info I want,
What are the acceptable piston ring gaps for a 3.9, bores have come out around 3.679/80, 93.48, so the 93.5 normal bore is very slightly undersize.
Ive had my block honed, not come out too bad really, all I can see in the bores is a small nick in the bore at the bottom, probably caused by a rod bolt when assembling the engine, If its not below the ring line, I will be surprised, and even if it is, tuff, its staying like that

For a 94.0mm bore, for both 3.9 and 4.2 litre engines.

Ring fitted gap :
Top Compression 0.44 to 0.57mm 0.02 to 0.022 in
2nd Compression 0.44 to 0.57mm 0.02 to 0.022 in
Oil control rails 0.38 to 1.40mm 0.014 to 0.05in

From the Land Rover engine manual 1997.