Charcoal Cannister deletion and fuel tank pressure

[SC400TT]

Gents,

I needed a strategic place to locate my catch can, so I removed the charcoal cannister, separated the mounting brqcket from it, and I mounted it to my Greddy catch can. I then mounted the catch can in that location. I currently have the line from the tank to the engine bay blocked off. I was always planning to go back and fab up a miniature catch can with charcoal in it and mount it in a place where convenient in the engine bay and run the line to it. I figured I would use the small plumbing container David used to make his cool little catch can with.

So, my question is:

1) Is this necessary to have a fabbed up cannister, or can I leave the blocked off tube blocked off?

2) I have heard that much pressure can build in the tank and actually cause it to expand, and over time, crack the fuel tank due to repeated expanding and contracting.

3) Can I simply add a vented cap? But, won't that make the garage smell?

I appreciate your thoughts guys.

Ryan

 

[BlackUZZ31]

mount the charcoal canister in the boot and just run the vac hose forward

 

[BlackUZZ31]

p.s. a non-vented tank will also screw with your fuel mixtures... (higher pressure at the injectors due to tank being under pressure when hot..)

 

[cribbj]

Ryan, +1 to blackuzz31's comments about fuel pressure. Not sure I would mount the canister in the trunk but if that's the only place, go for it.

I had a similar problem when I singled my Supra, and initially eliminated the charcoal canister. I ran an open vent line from the tank to atmosphere, but couldn't stand the stink in the garage, so I remounted the charcoal canister and ran its vent line to a point just after the air filter. There's just enough negative pressure at that point to keep the tank and canister vented and happy, but not so much to screw with the fuel pressure, plus it's far enough "into" the system to keep from stinking up the garage.

You might be able to eliminate the charcoal canister and vent the tank directly to the air filter, however I would think this through carefully before doing it, as a backfire through the intake could have disastrous consequences, especially if a backfire happened to ignite fumes in that line from the tank...... At minimum, I'd put a spark arrestor on that line, and possibly some overpressure protection, such as a very low cracking pressure check valve. The check would open with negative pressure at the air filter (hard acceleration), but would close at idle and if there was positive pressure (backfiring) in the system.

 

[brawls43]

Ryan, What did you end up doing? I was thinking about deleting the carbon canister completely, venting to atmosphere during racing, then capping when its parked in the garage.

 

[XR8tt]

Not a Lexus..
Mine is vented between air cleaner and turbo..
There is still one hose connected to inlet with one way
valve.. I assume it has always been there ???
When it wasn't connected the garage would smell of fuel..

 

[Cobber]

I run a carbon canister mounted in the boot vented to atmosphere below the car. No issues, no smell. Carbon canister flows both directions so you don't need a vented cap.

 

[BlackUZZ31]

I run a carbon canister mounted in the boot vented to atmosphere below the car. No issues, no smell. Carbon canister flows both directions so you don't need a vented cap.

Ohhh man there go's another box of tissues and a sore wrist! stop posting suggestive shots of your car!!!