6.4 or 5.7?

I haven't been on here in like 10 years. After kids, divorce and years of bodywork I should get my duster soon and be ready to take the next step.

I always planned on putting a 5.7l Gen III hemi in my car, but it seems that the 6.4 seems to be whats taking over now. What seems to be the consensus? I am looking to run AC and Power steering as well as a 6 speed manual. I would love to be in the 500hp club but drive-ability is more important.

The plan is reading up as much as I can but any quick help would be appreciated.

Lastly what is the best transmission for the 5.7 or 6.4?

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