A few thoughts, but I'm FAR from an expert with TBs... especially on these cars.
- Air has mass, therefor inertia
- With no changes other than a TB, you're going to have the same air charge (presuming that you weren't choked down before???)
- The SAME air mass through a larger diameter hole WILL move slower, therefor less inertia.
I can say that when I used to try to tune my bikes, OFTEN a larger carb would result in less power. Not really all that comparable, but it is at least a thought.
My final thought is that I bet this is on a bell-curve, and I doubt that Dodge choked down this engine when they were designing it. That is they probably made that TB big enough to give full power under idea conditions, and probably then some more.
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