rubber intake vs billet intake vs billet w/crossover

[bansheeqc]

Hi,

 

I actually use 36mm rubber intake boots and i want to know what is the difference between

 

Rubber intake boots

 

billet intake manifold without crossover tube

 

billet intake manifold with crossover tube

 

 

this manifold as the same or different effect on my engine?

 

With crossover, i will expect to gain some HP,TQ or any other thing?

 

 

thank you