i was reading that some people eliminate the vapor tank and plug up the unneeded openings on the fule tank . if i do this do i need to have a charcoal canister mounted in the engine compartment ?

I don't have one .

I had the Webers installed and the mechanic left the line to the engine compartment open, as the manifolds diidn't have a fitting for the vapor return line. Didn't seem to hurt anything and never had a fume problem. so may not be necessary for the cannister

The vapor tank and vapr canister work together. The vapor tank condenses the majority of gas vapor right off the fuel tank, and the vapor canistor gets what little is left, so you don't have the fumes.

Search for other threads on this topic to see what people have done.

TomoHawk, what you're saying is more applicable to the EFI cars, like ours, where due to the higher fuel pressure, the cannister is more of a necessity. I've seen quite a few carbed cars without a vapor tank or charcoal cannister without the problem of fumes.

Good point, Mike let us know what year car you have and put it on your profie, that will help

TomoHawk, what you're saying is more applicable to the EFI cars, like ours, where due to the higher fuel pressure, the cannister is more of a necessity. I've seen quite a few carbed cars without a vapor tank or charcoal cannister without the problem of fumes.

Stephen is quite correct. In fact, 240Z's didn't have a charcoal canister until the 73 model year in North America.

why would you need a charcoal canister? Don't eliminate none of that stuff on FI--

Check out technical articles.

Its a common thing to remove the old plastic vapor tank. Somewhere in the system, it is advisible to have a tank vent....collapsed tanks are not much fun! What I did was to fabricate a vent in the gas cap that also prevents fuel from slosching out when G-loads are present from cornering.

I'll play a little devils advocate here on this one. Do you NEED one? No. Is it a good idea? Yeah. the whole idea of vent canisters is for keeping gasoline vapors from escaping into the atmoshphere - a good, no great idea, especially if you want to think "green". Every "modern" car has them in one sense or another, a sealed fuel system. It doesn't effect performance in any way and personally I think it's a good idea to keep it in place if you already have one. If you don't, and like many here do you only drive your Z for pleasure, you can "justify" not needing one simply because if the fact that not too many still drive old cars like we do. OTOH, it's a good thing to do for no other reason than to realize that having gas powered "toys" to play with is a luxury we may not have for too much longer, and we should at least try to do what we can to extend what time we have to enjoy this luxury as best we can. I know it's a very "PC" attitude to take, but there it is. JMHO

well im actually running a v8 in a 240 with a 4 barrel and usually you dont need them but i was just curious cause i purchased my tank with all the holes plugged but the top one to the rear which i figured goes to the filler neck .and i just wanted to be sure before i put everything back together . a vented gas cap sounds like a good idea is there one that can be purchased like a universal or one from a later model maybe ?

The fuel vapor tank is made out of metal in 240z's.

Check out my tech article:

http://www.classiczcars.com/forums/showthread.php?t=19034

It mainly deals with POR15'ing the entire gas tank, but also explains how to reroute the fuel tank hoses correctly when removing the vapor tank.