Factory EEC systems, differences in fuel tanks, vapor lock, fuel return line or not

[71CHEVYSHORTBED402]

Interesting thread here. http://67-72chevytrucks.com/vboard/s...318544&page=32


I suspect 72 tanks were the same as 71?????? Still don't understand why a 71 gas cap differs from a 72.

On a side, to date I've yet to hear of a repop. vapor canister to suit. You'd think they'd be available, GM used mostly the same cans on 70-72............................Edit:, this link may clear that up some. He describes this beautiful cap as having a pressure relief valve. That doesn't sound like your everyday vent cap. Difference being a vent cap vents, while this cap blows when it has to..........Hmm........A provision where a vapor line fails? http://67-72chevytrucks.com/vboard/s...d.php?t=745146