Which engine is Cooler?

I voted for the 6.4 thinking, a 440 was offered in them so that's no fun and predictable. The V10 seems like head aches and a lack of after market or even OEM parts. The hemi however they make every day.

BUT! if it was mine,
used Nascar R5P7 for around $8k and find a circle track stick trans, quick change rear end and now you have a jaw dropper! Just my thoughts