So, I'm doing the infamous "engine bay clean up" and I have all emissions stuff removed besides the charcoal/vapor canister. So, logic tells me, plus some common sense, to just run the fuel lines straight to the primary and secondary fuel rails. Am I wrong here? Or is there more to it? Logic also tells me, it's never that simple. Help out a guy who let his S5 TII sit untouched for 2+ years and now finally has the bug up his *** to get **** done on it.

 

If you remove your charcoal canister you will have to do something with your vent lines from the engine and gas tank.

Let's start with the ones on the engine...

The breather vent hose for the engine can go to a catch can which you will have to buy, or make, then fabricate a mount for, then find a place to mount. Then depending on how much blow by you have (my guess is a lot, because reasons) you'll have to empty it periodically. You could run just a breather filter on your engine, then it will be covered in oil and goo all the time (which it probably already is.)

As for the fuel tank vent, you have to figure out where you want your fuel tank to evaporate fuel fumes to. If you want, you can disconnect the vent line from the tank and let it vent to atmosphere so the rear of the car will presents an even greater fire/explosion hazard than it did before. Or you could vent it under the hood, if you prefer to smell gas all the time while you drive down the road. There are probably some more clever methods for eliminating a fuel vapor eliminator, but as of now I'm fairly certain that the charcoal cannister is the best fuel vapor eliminator eliminator... eliminator. Ahem. 😐

As for your fuel lines, I assume you're getting rid of the "rats nest" and wanting to clamp the supply and return hoses directly to the barbs on the rails and running them directly from the filter and to the return hard line? Just be cautious of what type of hose you replace them with, how you route it, how tight or loose they fit, and keep an eye out for leaks.
(Which are very difficult to pin-point by smell once the charcoal cannister is removed.)
You need adequate length of hose that fits the barbs tightly, is rated for both the type of fuel and pressure you will be running, and you need the right hose clamps. Worm clamps suck. Actually, from my experience, all hose clamps suck. AN or JIS fittings rule. I eliminated all of my fuel related hose clamps with fittings from Jegs. All my fuel connections are threaded flare connections (AN -6.) I haven't had a fuel leak since. Good luck.

 

There's some very useful info and diagrams on different ways to set up a breather with and without PCV or catch can in this topic: How to properly setup an oil catch can (Bumpstarts Guide) - AusRotary

 

^ That is a very well thought out guide.