How does upgrading a throttle body create more power? Or does it just free up power? Does that justify the price that they go for?

 

A TB makes power by being able to supply more air to the engine. It only works if you have the need for the air, like big cams, ported head and a bigger intakemanifold. For the most part its not worth the money unless the rest is already done first. You can even disrupt proper air flow and loose more power than gain.

 

bout the only thing "worthwhile" it will do to a stock motor is increase throttle response.

 

not necessarily. I have seen larger TB's actually decrease performance when not planned/matched with entire setup.

Just something to keep in mind also...