Fuel system hose sizes?

[71CHEVYSHORTBED402]

Originally Posted by 58 Special

I think only 1972 have the canister in front. all others are vented through the cap.
If I'm wrong I will be corrected. I'm used to it.

Well.............

Barring situations the factory isn't using up former stock or moving onto new materials, identified by "ish" - I'm pretty sure the 1970ish-1971 cap only vents when there's high pressure in the system, where the canister isn't cutting it, while the 1972ish cap vents more often under less pressure.

The cannisters were installed in 1970ish ending I don't know, 1980s?

I wonder how old tanks vented, 1970ish and before? I assume the caps.

Reading above, I didn't know the old hoses may not be ethanol proof. - Personally my 71 truck has EEC/Fuel hoses that came with these trucks, but I installed a regular fuel hose from the hardline to the fuel pump. I only use ethanol free fuel, so far no problems since the restoration, without a fuel return line the factory began installing with certain transmissions, beginning 1972-ish. My 400TH is one of those transmissions.