it still only has 8 coils. its just like the srt engines...one coil does both plugs in the same cylinder.
That is what I was thinking, it is only one coil with a plug running to the second one and both plugs are in the top end of the motor. If they do fit but the coils wouldn't work couldn't you just run the old coils and run only one plug (with the other just filling the hole). From what I have read, it seems to me that the second plug is more for emissions then performance.
Also, other then the bump in compression, intake manifold, and lighter internals, it seems like a big difference between them is in the heads and I've seen entire long blocks selling for cheaper then ported old 4.7 heads. I'm thinking that if the heads could be swapped it could be a nice gain in performance.
Even if the heads won't fit I wonder if you could run the motor off the older computer? With them being so new I don't see it being very easy to get heads without getting the entire motor and more then likely if I ever tear that far into my motor the entire thing will come out for pistons and rods (and I have a spare block sitting in my barn).
The bottom end doesn't look all that different.
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