Vented Gas Cap???

[90Fox]

Ok me and my old man just purchased a 90 GT with a Vortec suprcharger on it. The previous owner had it tuned by someone in Maryland and he had drilled 2 small holes in the gas cap. I was told the reason for this was because due to the bigger fuel pump there wasn't enough air flow and thats why this was done. I personally have boosted cars and put bigger fuel pumps in and have never heard of this so my questions to all of you is: Is this a common thing??? Does anyone else have this done and could further explain???

Thanks,
Matt

[Rio94gt]

I was pushing 17 pounds of boost from a vortech in a 94' GT, 255 pump, t-Rex, and 60 pound injectors and I didnt drill any holes in my gas cap nor was I told to do so by SGS automotive who tuned the car.

[90Fox]

I personaly have never heard of this being done either and don't understand the reasoning for it. I figured I'd ask on here and hope to get some incite and answers. To me it doesn't make much sense. Thanks for the comments Rio94gt

[frankstang]

Never heard of anyone doing that. 5.0's came with vented gas caps from the factory, so I don't understand the reasoning behind drilling holes in it.
Are the charcoal canister and vent line from the tank still on the car, (left side of engine compartment below the headlight on the framerail) ?
Only thing I can figure is they removed the canister and line, so they made a home made vent system ??