'79 Vapor (Charcoal) Canister Connections?
 

I have a 1979 Corvette L-48 with a full top-end rebuild. I no longer have emissions and have a Holley 4175 instead of the Qjet. I know I still need to vent the full tank vapor but is it still worth it to connect the Vapor (Charcoal) Canister to the Carb even though the emissions components are no longer installed and functioning? My best guess would be to keep the canister in place with the full tank line in place and plug the remaining ports on the canister except the one that would go to the carb fuel bowl and just vent that by keeping it open to atmosphere. Curious what the right thing to do would be so that I don't get that abundant fuel smell yet don't impact vacuum and vehicle performance.

All connections to the canister remain in place except the one that connects to the EGR valve line which no longer exists so I plugged that port on the canister. That port is labeled Control Vac. I'm just hoping it does not control the removal of vapors from the canister and it's still functional. I'm guessing so since I do not smell fuel in my garage.

Since your Holley does not have an external bowl vent connection, I would plug that one off on the canister. Yes the control connection is the one that opens the purge valve on top of the canister and allow the vapors to enter the intake manifold.

If your asking about fuel smell in a garage, there is not likely enough temperature gain inside to cause a lot of vapor production. Outside in the sun is a different matter.

The charcoal canister rarely causes a performance problem. The main failure would be a purge valve diaphragm rupture which could cause a vacuum to be placed on the gas tank causing liquid fuel to enter the canister and then flooding the engine.

Incorrect. I do have an external bowl vent connection. But without the connection to the Control Vac port I'm guessing the canister and connections are now rendered useless?

Is it this style of bowl vent?

http://ep.yimg.com/ay/spideraccessor...rburetor-2.gif

It would be hard to put a hose on that

Did you decide to pull the canister? I unscrewed my canister from the fender last night but didn't see a way to actually get it out from its spot. I want to place a vacuum tank in its place. Didn't look from the underside yet.

At the bottom of the fender well there is a removable plate that will let you access the canister. Four bolts. You will have to remove the side skirt ta access two of the bolts. Only remove the canister if you have removed your emissions. The Vapor Canister is actually a good thing. If you have a 75 - 80 and remove the canister you will want to install a vented gas cap.

At first I was relieved, then I remembered that the last time I tried to remove the side skirt I couldn't because the screws are stuck and started to strip!

Yeah this car has no emissions at all. Headers > pipe > mufflers. Super vic intake and holley double pumper.

Thanks for the info, I'll hit the screws with some pb blaster.

There was only return line plugged to charcoal .and I noticed the pure fuel was raining like shower under the charcoal at the gas station .at 4 am I was trying to figure it out then took the return line and plugged it up .what a night it was lol