Ok here is what's going on I have a 6.9 that I pulled out of the truck and is in waiting for rebuild the one of the heads might be junk I am buying almost ready to drop in 7.3 I have read that the 7.3 heads have a few differences. I ask because when I am almost finished rebuilding the 6.9 will the heads off the 7.3 work? I plan on putting arp head stud kit on the rebuilt 6.9 because I plan on putting a hypermax turbo kit on it

 

6.9's use 7/16" head bolts, and 7.3's use 1/2". Makes it hard to swap heads. I seem to recall there being some differences in coolant passages too.

 

How different is the coolant passages? I think the head bolt holes in the 6.9 block can be enlarged

 

The thread pitch is different, so enlargeing the 6.9 to the 7.3 1/2 inch head bolt won't work.

 

I recall someone looking into see if 9/16" studs would work, not sure what the result was. General consensus was there would be too much cylinder deflection.

 

If you are "rebuilding" the 6.9 why even think about 7.3 heads?? That is part of rebuilding you have the heads done! Or am I missing something?? IDI's cost to much money to rebuild so if you are going to only do it halfway just stop and save your money you will end up having to just redo it again and cost double the money later.

 

No it's getting a full rebuild I think one of the 6.9 heads are junk it had 3 burnt valves and a small crack next to the pre chamber I was just hoping I would be able to get the 7.3 heads redone when I finished the rebuild and stick them on if the 6.9 head is actually bad

 

You can get pretty nice fully redone 6.9 heads for (last time I checked) for 224.00 each shipped!!