Sending unit vapor line on 81 malibu

i have a 1981 chevy malibu with a 350 bored over 60 and a comp cam and i wanted to no if my car needed the vapor return line the engine is modified and there is no charcoal canister the line just runs and ends under the wheel well on the driver side. and if not do i remove the line and plug it off from the sending unit and get a vented gas cap thanks in advance.

or can i leave the vaper line open on top of the tank like a short vent line

The .060 over bore and comp(?) cam don’t really have much relevance I don’t believe. For your own safety and with the slightest modicum of concern for spewing fuel vapor into the atmosphere, you might consider attaching the tank vent line to the breather housing. Is this a street vehicle?

To get the greatest bang for the buck in automobile modifications it pays to learn the basics first. Don’t be too impressed with the big numbers in magazine ads. A high torque RV camshaft will make a Malibu perform better on the street than a competition cam.

yes this is a street vehical, it is a project and im not driving it yet that y im trying to make sure about this before i do. i bought this car and am going behind to fix the little stuff. it doesnt have a charcoal canister for the vapoer line to plug into thats y i need to no what to do with the line. and what breather housing if thats the canister under the hood its not there. thanks for your help.

This I would not do. You want the fumes to be vented away from the underside of the vehicle. You mentioned the more common approach- most people plug the vapor line and use a vented gas cap. This is the way they ran for many years and having a few cars running like this now is not going to destroy the earth IMHO…

what i ended up doing was putting a filter on the line right after the tank and left rubber hose at the end so i can plug it if needed my gas cap is vented so ill probably end up pluging it off thanks for the help.