Fuel cap

[NatesIH]

Quick question now that my FI is up and running. Rather beautifully I might add.
With the return line required, it seems quite a bit of pressure builds in the tank. I have a nonvented locking gas cap and just want to be sure I should not switch to a vented. It runs great and doesn't seem to make a difference. Just want to double check with someone.

 

[ihpartsjeff]

The fuel tank needs to vent whether its thru the charcoal canister or a vented gas cap. I would start with the vented gas cap since its cheap and easy.

 

[Bill USN-1]

Something to keep in mind is the venting cap prevents a vacuum in the tank but it will still create pressure.
The vent is one way.
Just go to the parts store and stick one up to your mouth and try it.