CIS/Turbo hoses to Intake?
 

There are two hoses which connect to the CIS intake Box. One is about 3/4" the other is 1/4"; What is the proper function of these hoses? do these need to have vacuum from the intake?
On some aftermarket air filter systems I have seen that these are capped off with their own filter, which means they would not get any "draw" from the intake.

The larger hose goes to the oil tank. That is where you get the mess from hell when an overfull tank burps over.

I can't remember off the top of my head where the smaller hose goes to. Might be smog equipment. I 'll look when I get home tonight.

The 3/4" hose comes from the oil catch tank, you can remove it and use a breather. This way you won't get oil in the intake and reduce the octane rating. The smaller one I believe is for emissions where it sucks fuel vapors back in to be burned instead of venting to atmosphere.

Thats what I needed to know! So the 3/4" line actually sucks filtered air in? How would it fight against the vacuum created by the intake?

No, it will vent oil vapors from the oil tank and catch tank. It's just a good idea to put a breather there. Not sure what you mean by fighting against vacuum created by the intake?

What I meant is that if it is attached to the intake then air will get drawn out as the air moves past it into the engine. If it is standalone then there is nothing to pull the vapor out and it would probably not go anywhere.

The vapors will still come out without any vacuum and even some oil too.