Depends on what you go for nozzle sizes. If you run a DO3 nozzle its going to all evaporate before it hits the cylinders. This is what makes the cooler intake air charge.
Something like this your not going to need to change anything.
When you start running larger nozzles like a DO5 you might need to pull a slight amount of fuel to get your o2 back where they need to be.
Bio248
Check valves are a 1 way valve. Evey check valve has a spring in it that does not let fluid flow thur it at ALL till pressure is above the spring pressure. this is commonly referred to as crack pressure. The key to this is it has to have a min of 15psi of crack so it can handle 30inch of vaccum that a car presents at an idle and not open.
