fuel vapor line question
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From: Woodland, CA
Car: '02 Z06
Engine: L33 5.7
Transmission: T56
Axle/Gears: Stock IRS
fuel vapor line question
since i removed my charcoal canister, hows the idea sound to run the vapor line from the tank straight to the throttle body where the charcoal canister line used to run? so i pick up those extra fumes, and in theory, keep any gas milage i might lose.
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From: Woodland, CA
Car: '02 Z06
Engine: L33 5.7
Transmission: T56
Axle/Gears: Stock IRS
well ive read of some people just venting it through a filter or under the car, so i thought, what if i put the line straight to the throttle body?
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From: Moorestown, NJ
Car: 88 Camaro SC
Engine: SFI'd 350
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I wouldnt. Itll suck all the fumes right out of the tank and pull them into the engine if you hook it up to a vacuum port on the tb. Use a breather instead.
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From: Gambrills, Md
Car: clapped out 84Z
Engine: 355 efi roller
Transmission: tremec TKO
Not to be **** or anything, but are you still running the stock ECM?
If so, it will control purging the vapors into the engine. All a breather will do is vent the vapors into the atmosphere (you will smell lots of gas fumes). Why did you remove it?
If so, it will control purging the vapors into the engine. All a breather will do is vent the vapors into the atmosphere (you will smell lots of gas fumes). Why did you remove it?
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From: Woodland, CA
Car: '02 Z06
Engine: L33 5.7
Transmission: T56
Axle/Gears: Stock IRS
i mainly removed it, in my goal to make the engine bay as simple as possible. and yes i have stock ecm 
i see both your points lo-tec and dimented4x4. but which is is true? i can see hwo the vapors would always get sucked in because of vacuum from the manifold but..

i see both your points lo-tec and dimented4x4. but which is is true? i can see hwo the vapors would always get sucked in because of vacuum from the manifold but..
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From: Gambrills, Md
Car: clapped out 84Z
Engine: 355 efi roller
Transmission: tremec TKO
I would remote mount it onto the front bumper reinforcement, underneath the plastic cover by the core support. That's where mine is. Lengthen the hoses and electrical connectors.
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From: Seattle
Car: Which one?
Engine: 355
Transmission: 465
I ran my carbed car like that for a long time, before I knew better. (at least I think so now)
First off, you don't really want the vapors from the tank going into the engine all the time. Second, you have no check valve. I would *assume* that if something happens, you MIGHT be able to ignite that whole system. Nothing between the tank and ignition source (like a check valve) scares me. Air/fuel ratio in the tank is probably too high in most conditions to even ignite, but you can't get much more dangerous than fuel vapor.
I don't like the venting idea very much either, that is always going to be a source for ignition AND corrosion as well. I can't think of one place on my vehicle that I want fuel vapor coming out of. Not only that, it's going to be pretty hard to keep the vent line from being a source to introduce water into the tank from humidity, and that wreaks havoc on the tank, sender, fuel, etc.
Fuel is one of the things you don't play around with on a car.
If I were making an EVAP setup I'd like to see it with one line in from the tank, one line out from the cannister to engine, and a switch of some kind (vacuum, thermal, ECM) controlling when the engine gets the vapor. It would be simple, safe, and more importantly, clean.
First off, you don't really want the vapors from the tank going into the engine all the time. Second, you have no check valve. I would *assume* that if something happens, you MIGHT be able to ignite that whole system. Nothing between the tank and ignition source (like a check valve) scares me. Air/fuel ratio in the tank is probably too high in most conditions to even ignite, but you can't get much more dangerous than fuel vapor.
I don't like the venting idea very much either, that is always going to be a source for ignition AND corrosion as well. I can't think of one place on my vehicle that I want fuel vapor coming out of. Not only that, it's going to be pretty hard to keep the vent line from being a source to introduce water into the tank from humidity, and that wreaks havoc on the tank, sender, fuel, etc.
Fuel is one of the things you don't play around with on a car.
If I were making an EVAP setup I'd like to see it with one line in from the tank, one line out from the cannister to engine, and a switch of some kind (vacuum, thermal, ECM) controlling when the engine gets the vapor. It would be simple, safe, and more importantly, clean.
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