What Palmer said is true about plugging the vents to the float bowls. Clean air is important , this is another reason to vent them into the air cleaner. Now to your question of vacuum lines . The front carb. has a port that is for the vacuum advance on the Dist. , one line must go to the vacuum booster on the master cylinder. The vent line with the PVC valve comes from the block and is attached to the intake balance tube. The vent from the valve cover is supposed to also connect to the air cleaner. If you add one of the little cute filters to this vent it is likely you will have fumes in the cabin. When run into the air cleaner the engine will burn these fumes. The stock air box has tuned velocity stacks installed for performance also , another reason to use it. One more thing , there is a fresh air return line that runs form the gas tank to the front of the car. It runs to the driver side up to where the ignition coil area is. On a 240 it connects to a divert valve . One small 1/4'' hose connects to the air cleaner and supplies fresh clean air to the main fuel tank as needed , one connects to the crankcase vent . This little valve is a one way valve that allows air to the tank and will restrict flow from the tank. If this is blocked the fuel tank will starve for air as the gas is drawn to the engine. Unless the seal is bad on the gas cap. If you don't use this valve or do not run the supply line to a clean air source dirt will be drawn into the tank. Be SURE to use gas rated fuel line , not vacuum line for all gasoline use. Injection rated gas line is not necessary because you are only dealing with at most 5 psi. Gary The OEM fuel rail has a function as a metering of the return line to the tank. The return line is important so that cool gas keeps running through the supply to prevent ''vapor lock'' .

Across the board, front to back, top to bottom, good information all on this topic. A lot of internet info is worth exactly what is charged, but this time y'all nailed it!!

My dist. has no vacuum advance. jeez... Im going to end up spending another $300 just on crap I need to make these carbs work. Oh, and I make my custom fuel lines from bulk brake lines, will that work?

My dist. has no vacuum advance. jeez... Im going to end up spending another $300 just on crap I need to make these carbs work. Oh, and I make my custom fuel lines from bulk brake lines, will that work?

The vacuum advance has nothing to do with making the carbs work. It has to do with making the distributor work. The front carb is just the source of the vacuum. If your distributor does not have a vacuum advance then just plug the small hole in the carb.

Well, I finally got around to putting the carbs on. All I did was bolt 'em on, and start it and it runs fine. It idles rough, but maybe thats because it has no air filter and the carbs need a good tune.

And I put on my other hood (it has no hole)

hey just read this thread, im doing the same kind of thing to my car. Enigma i noticed in the pic u posted, the fuel rail had no heat protection, is this a problem?cheers

Fuzz

justin - you might want to put thicker carb spacers on...also, get the ZTherapy carb video. worth every penny.. and then some! i also noticed the lack of a fuel return line. i woule address that

fuzz - the early 240zs didn't have heat protection on the fuel rai from the factory. they seem to be ok with little to no vapour lock