Sorry, i don't know the name of this bar, but it looks to me like a brace that is mounted to each side of the car inside the engine compartment that goes straight across and is higher than the engine.

What is this called and what does it do? i've seen these on a lot of cars, but never really understood the need for it.

 

strut tower brace or STB, it ties each strut tower together to decrease flex, it aids in handleing.

 

A STB is one of the items that improves handeling & tightens the font end up. It should be one of your first supension Mods,

 

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two types that i know of.

two point stb (shown in the pics) and also the
three point stb (which also connects to the firewall).