zenon222

The Gen 4 4.8 are the exact same block with a shorter crank?

G Atsma

Yes. The 5.3 and 4.8 engines use the same block. Different stroke only.

Steve - Race Eng

iTrader: (1)

LS1 LS6 bore size 3.897" would be max. bore on the stock sleeves. If the block is casting #12571048 or 12601900 it can be sleeved with Darton LS7 dry liners for bores up to 4.185" as someone stated. Depends on your budget. Least expensive route would be to bore your block, stroke it and top off with a set of Air Flow Research or Trick Flow heads with cam, intake, headers, etc.