Keep in mind that Hughes build their CNC ported Pre-Eagle heads flow 347I 166E@650 Lift....so with Eagle, Apache, or Edelbrock heads you will make more HP, the only question is going to be where will that HO be in the RPM band....the high you spin it the better the rockers have to be.

These G3's can make a dump load of power with less cam than the same Cubic inch LS engines...the LS engine NA advantage right now is RPM.

I have some Apaches for sale in the classifieds.

I’m interested in the 3rd stuff as well just hard to step out there and try one especially on my budget
Really have considered buying a 6.4 using a Ritter intake and putting it in my dart just to see how fast it will go with supporting mods ie cam exhaust
Those Apache heads are very attractive

To early for me as I have a W7 combo that I need to buy heads for first. The nice thing about the gen 3’s is new stuff is coming out everyday so it’s kinda senceless to stock pile parts to early.

Are there differences in 6.4 we should avoid?

MDS or Non MDS is about it. A lot of people want to get rid of those lifters but haven't seen any issues myself out of them

6.4 truck engines are built with better parts, Hellcat block, Hellcat type heads, beefier crank/rods, maight have forged pistons

If I were to build one for sure it would have an aftermarket crank, rods, and pistons.

I've been 9.74@137 in a 392" 3400# dart with 4.10 gears.

I have more than $8K in mine, but you could certainly save money by not buying stuff like $1000 headers and $800 water pumps that I like haha.

triple what is your build like?

But you have less overall in the engine.
Meaning if you were to run those #s in an LA it would be more $$ .
Impressive!