Gas cap question.

[69427]

I've been using an aftermarket locking gas cap on my '69 for years, but I'm thinking on putting the stock cap back on. I just looked at it, and I don't see any vent hole on it (my locking cap has a small vent hole in it). Am I missing something (this is the cap that was on the car when I bought it), or how does the tank replace the air volume when the fuel is pumped out during use?

Sorry for the stupid question, but I'm damn curious.

thanks,
Mike

 

[mrvette]

Locking cap with the EVP? charcoal filter is fine....

honestly, I dunno we even need the charcoal canister....

the prime vent of it into the engine is direct mani controlled as we know, but the valve on my system seems fine with the small control line removed...because it's blocked open...so to the above throttle blade like a crank breather hose to the air cleaner...same thing, above the throttle bodies....and with the vented cap, it's been years since even my wife has smelled gas....

and not THAT kind either, just the type Exxon sells....

:yahoo:

 

[68/70Vette]

The stock vented cap doesn't have a vent hole, but when you snap it on, it's not air tight. There's a vent path in the inside of the cap. Don't know how to describe it.