6.9 modification
Elder User
Joined: Mar 2010
Posts: 637
Likes: 0
one of the more experinced guys will chime in in a minute but I think the're gonna tell you that the heads will fit but boring it out is just inviting trouble, not that bad though the heads gain more power than the bore job would
Cargo Master
Joined: Mar 2006
Posts: 2,789
Likes: 5
From: Sand GAp, KY
The heads on the 6.9 have bolt holes for a 7/16" bolts, the 7.3 has them for 1/2 bolts. I am not sure if you can get washers (they are hardened) that will let you use the 7/16" bolts with the bigger holes.
Post Fiend
Joined: Oct 2007
Posts: 10,501
Likes: 5
From: Faibanks Ak.
The heads wont swap, I suppose you might be able to bore a 6.9 that much, but I wouldn't, as that is why I prefer the 6.9 over the 7.3. You can bore the 6.9 several times and still have better cylinder walls than a new 7.3.
