Forced Performance intake question

my98GST · 08-22-2006, 03:32 PM

My buddy has a FP 4" intake that he was going to use on his 14b but it kept hitting the J pipe. I have an Injen 3" intake and was thinking about trading him for it. I noticed on his intake, it doesn' t have the vacuum nipples. I know I don't really need the one coming from the valve cover or the one on the front of the intake that has to do with the BCS, but the one coming from behind the battery, whats that for? Would I need to install something to allow it to work? Or do I even need it?

JayRolla · 08-22-2006, 03:38 PM

Actually the one behind the battery is the charcoal canister and you really dont need that one, just plug it up. The one from the valve cover if you dont run it to the intake it can change your airfuel mixture and make you run lean, this is the one you really want to keep hooked up. But if you have a fuel controller you can adjust for it.

my98GST · 08-22-2006, 03:48 PM

Alright so the big fat one that plugs into the back of the intake by the MAS is for the charcoal canister for which I don't even have so I don't need it? Just throw a screw in it and clamp it off? The valve cover one I have inline with a Purolator fuel pump as a oil catch can going back into the intake. I have an SAFC so I suppose there wont be a problem.

2gGSX · 08-22-2006, 03:56 PM

Quote:

Originally Posted by JayRolla

Actually the one behind the battery is the charcoal canister and you really dont need that one, just plug it up. The one from the valve cover if you dont run it to the intake it can change your airfuel mixture and make you run lean, this is the one you really want to keep hooked up. But if you have a fuel controller you can adjust for it.

This is incorrect, the one connected to the valve cover is valve cover breather hose. It usually lets clean air through the valve cover and out the PCV valve, but it also releases excessive crankcase pressure in the form of oil-y air. You don't need this one connected to the intake at all, and it can be replaced with a filter and/or catch can.

JayRolla · 08-22-2006, 07:30 PM

Yes I know its the breather hose. There is huge debate on if it does or doesnt change the air fuel mixture. But it was proven some have no problem and others do have problems. I think it was Steve the wiseman that told me this.

No_Skillz · 08-22-2006, 10:18 PM

Using a plain filter or a closed catch can on the VC breather not only will affect a/f off boost, but it will also take away the circulation properties of the VC breather and PCV valve system. This can lead to fuel soaked oil, which can be a big problem. For more info on the PCV and VC breather system, do a search.

JayRolla · 08-23-2006, 08:59 AM

Thanks No Skillz for the response. I knew I want incorrect.