OK I'M STILL UNSURE ABOUT THIS....................................
it's the manifold that won't clear the hood right? NOT the B20 head/valve cover right?

 

One of the b20 models has an intake manifold similar to the LS manifold. The other model has the tunnel ram style intake manifold that will not clear the hood.

 

THANKS MUCH

 

If i'm not mistaken:

b20b has the giraffe tall intake manifold that won't clear the hood.

b20z has the intake mani similar to the b18a/b

 

However, both the B20 manifolds make less power than an LS on the B20 does.

 

so which one do i use(going to a 91 civic) 90 to 93 or 94+

 

It doesnt make a difference, as long as you get all the sensors with it. Dont go too new or else it wont have an intake temp sensor on it though (white sensor on one of the runners). If you go with a newer one, all you gotta do is extend your map sensor wires so they reach your new throttlebody mounted map. b

 

Although the B20Z intake manifold is similar to the LS manifold, it has a resonator box on top of it. It is very likely this will not fit under the hood, either.