i swaped a 95 LT1 into my car. do i need to somehow hook up the charcoal canister?
Supreme Member
Quote:
Originally posted by sinner
i swaped a 95 LT1 into my car. do i need to somehow hook up the charcoal canister?
You need a way to vent pressure from the gas tank. Before charcoal cannisters, cars just had vented gas caps. If you cap off the vent line, and run your stock unvented cap, the tank will build pressure and become unsafe.Originally posted by sinner
i swaped a 95 LT1 into my car. do i need to somehow hook up the charcoal canister?
the fuel line is still connected to the canister, but there is no longer the line going to the engine.
do i need to restore that connection?
is there a way to eliminate the canister if its not being used?
(a filter or something?)
do i need to restore that connection?
is there a way to eliminate the canister if its not being used?
(a filter or something?)
Supreme Member
You want to give the fumes a safe escape route, if the LT1 has an evap inlet you could connect that to your cannister.
My cannister was electrically-controlled, and the LS1 I was installing had an evap solenoid on the intake...had to pick one or the other as the switch.
So...I hit the junkyard, found a G-body car that had a cannister same size as mine but no controls...just an inlet and outlet. That works great w/ the LS1 evap solenoid, same size hose fittings and everything.
My cannister was electrically-controlled, and the LS1 I was installing had an evap solenoid on the intake...had to pick one or the other as the switch.
So...I hit the junkyard, found a G-body car that had a cannister same size as mine but no controls...just an inlet and outlet. That works great w/ the LS1 evap solenoid, same size hose fittings and everything.
mine used to be electronicly controlled too. hmm, so i need to find an LT1 guy to ask....so like, hmmm...where to look, what to doo....hahahahahahahaa:lala:
So is there a way to eliminate this cause i rather not have it if i dont have too.
Senior Member
OutLaw305
Senior Member
close
- Join DateJul 2002
- LocationSouth East MI
- Posts:754
- iTrader Positive Feedback0
- iTrader Feedback Score(0)
- Car1992 Camaro RS AKA Big Nasty
- EngineCarbed '79 350 block, 360hp/380ftlbs (flywheel)
- Transmission6speed from an unidentified 4th gen. ask me, ill tell you.
- Likes:0
- Liked:0 Times in 0 Posts
you think we could just use vented gas caps?
Supreme Member
I got rid of the entire thing. Canister, vent line, everything, and then capped off the vent line from the tank. I then removed the stock pressure relief valve and replaced it with a K&N breather with a stud that mounts right where the pressure refief valve did. Looks factory 

Supreme Member
Quote:
Originally posted by Spdfrk1990
Hmm sounds like a good idea work good so far? Possibly get some pics.
Works great, but no pics as of now. Possibly in the not so near future though.Originally posted by Spdfrk1990
Hmm sounds like a good idea work good so far? Possibly get some pics.
Yeh i would like to see that did you just get rid of that 1 vent line then and put a filter where that valve is by the rear brake line?
Supreme Member
Quote:
Originally posted by 25THRSS
I got rid of the entire thing. Canister, vent line, everything, and then capped off the vent line from the tank. I then removed the stock pressure relief valve and replaced it with a K&N breather with a stud that mounts right where the pressure refief valve did. Looks factory
So...you're venting gas fumes under the rear of the car, right near the exhaust?Originally posted by 25THRSS
I got rid of the entire thing. Canister, vent line, everything, and then capped off the vent line from the tank. I then removed the stock pressure relief valve and replaced it with a K&N breather with a stud that mounts right where the pressure refief valve did. Looks factory
One backfire during a hot restart, after the car's been sitting a while and built up a nice vapor cloud, should invoke a Darwin award.
Supreme Member
A vented gas cap would minimize the problem I raised above...it would vent vapors above the car, where they would dissipate.
Venting under the car, where the vapors can accumulate, is dangerous.
Venting under the car, where the vapors can accumulate, is dangerous.
Senior Member
OutLaw305
Senior Member
close
- Join DateJul 2002
- LocationSouth East MI
- Posts:754
- iTrader Positive Feedback0
- iTrader Feedback Score(0)
- Car1992 Camaro RS AKA Big Nasty
- EngineCarbed '79 350 block, 360hp/380ftlbs (flywheel)
- Transmission6speed from an unidentified 4th gen. ask me, ill tell you.
- Likes:0
- Liked:0 Times in 0 Posts
E-check. Whats an E-check?

ya we dont have those either
so anyhoo, i guess from all this i still dont know what to do.
do i remove the canister and put a filter on the line from the tank or do i find somewhere on the motor to hook up the canister?
if so where?
so anyhoo, i guess from all this i still dont know what to do.
do i remove the canister and put a filter on the line from the tank or do i find somewhere on the motor to hook up the canister?
if so where?
I was under the impression the charcoal canister only functions after the car is shutoff to recover fuel vapors left in the intake tract. When the car is started the next time, the canister is purged and the vaoprs are burned.
Supreme Member
Quote:
Originally posted by kevinc
So...you're venting gas fumes under the rear of the car, right near the exhaust?
One backfire during a hot restart, after the car's been sitting a while and built up a nice vapor cloud, should invoke a Darwin award.
The factory put the pressure relief valve right there. I highly doubt if it was so dangerous that they would do that. The exhaust doesn't get anywhere near hot enough that far towards the rear to ignite anything.Originally posted by kevinc
So...you're venting gas fumes under the rear of the car, right near the exhaust?
One backfire during a hot restart, after the car's been sitting a while and built up a nice vapor cloud, should invoke a Darwin award.
Supreme Member
Quote:
Originally posted by 25THRSS
The factory put the pressure relief valve right there. I highly doubt if it was so dangerous that they would do that. The exhaust doesn't get anywhere near hot enough that far towards the rear to ignite anything.
The factory did not intend for it to be venting at atmospheric pressure, full time, such as the design above would do.Originally posted by 25THRSS
The factory put the pressure relief valve right there. I highly doubt if it was so dangerous that they would do that. The exhaust doesn't get anywhere near hot enough that far towards the rear to ignite anything.
It's not exhaust pipe heat that would trigger an explosion, it's a tailpipe backfire during startup.
I'm not saying not to do it and I'm not too interesting in arguing beyond what I've posted...if that risk isn't enough to sway opinion, then by all means go for it. Darwin candidates have rights too.
Supreme Member
Quote:
Originally posted by kevinc
The factory did not intend for it to be venting at atmospheric pressure, full time, such as the design above would do.
It's not exhaust pipe heat that would trigger an explosion, it's a tailpipe backfire during startup.
I'm not saying not to do it and I'm not too interesting in arguing beyond what I've posted...if that risk isn't enough to sway opinion, then by all means go for it. Darwin candidates have rights too.
No, they just intended it to open under extreme pressure and vent a large amount of fuel vapors at an excelerated rate. Quit being an ***.Originally posted by kevinc
The factory did not intend for it to be venting at atmospheric pressure, full time, such as the design above would do.
It's not exhaust pipe heat that would trigger an explosion, it's a tailpipe backfire during startup.
I'm not saying not to do it and I'm not too interesting in arguing beyond what I've posted...if that risk isn't enough to sway opinion, then by all means go for it. Darwin candidates have rights too.
and how often are you going to get a tailpipe backfire on start up with enough fuel vapor underneath the car to start a fire or explosion?
Senior Member
OutLaw305
Senior Member
close
- Join DateJul 2002
- LocationSouth East MI
- Posts:754
- iTrader Positive Feedback0
- iTrader Feedback Score(0)
- Car1992 Camaro RS AKA Big Nasty
- EngineCarbed '79 350 block, 360hp/380ftlbs (flywheel)
- Transmission6speed from an unidentified 4th gen. ask me, ill tell you.
- Likes:0
- Liked:0 Times in 0 Posts
once in a lifetime? but still, would you risk it?
so...again..what do i do here? how do i resolve this issue?
Supreme Member
Quote:
Originally posted by 25THRSS
No, they just intended it to open under extreme pressure and vent a large amount of fuel vapors at an excelerated rate. Quit being an ***.
...says the guy who can't spell 'accelerated' but still feels qualified to give out advice...Originally posted by 25THRSS
No, they just intended it to open under extreme pressure and vent a large amount of fuel vapors at an excelerated rate. Quit being an ***.
With a functioning charcoal can, you will never, ever build enough pressure at the tank to open that vent. It's a safeguard to prevent the tank from popping in the event of a failure.
Supreme Member
Quote:
Originally posted by TexasLT1
and how often are you going to get a tailpipe backfire on start up with enough fuel vapor underneath the car to start a fire or explosion?
Check back w/ us on that when your Opti-Spark lets go. Originally posted by TexasLT1
and how often are you going to get a tailpipe backfire on start up with enough fuel vapor underneath the car to start a fire or explosion?

I'll take a swag and say neither GM nor the NHTSA have done failure mode effect analysis on the combo of hacked-up fuel systems and exhaust backfires, so there's not likely any statistically-valid data on that.
Gasoline in vapor form trapped under the car's body is incredibly dangerous stuff, just one flicked cigarette or brake pad worn down to metal-on-metal and you have an ignition source.
Again, this is one of those hacks that only puts the driver and occupants of the car at risk, so I'm not totally against it.

Quote:
Originally posted by kevinc
Check back w/ us on that when your Opti-Spark lets go.
Originally posted by kevinc
Check back w/ us on that when your Opti-Spark lets go.
I will. 80K+ miles and going strong. I'm not too worried
And the Opti is a known problem.
Fuel vapor under the car in large enough quantities to excite an explosion due to a rapid venting of built up pressure in the fuel tank during startup when a tail-pipe backfire occurs, not a known problem.
Supreme Member
Quote:
Originally posted by TexasLT1
Fuel vapor under the car in large enough quantities to excite an explosion due to a rapid venting of built up pressure in the fuel tank during startup when a tail-pipe backfire occurs, not a known problem.
Can't argue that, but it seems a safe assumption that ignition of captive fuel vapors is a real risk. Originally posted by TexasLT1
Fuel vapor under the car in large enough quantities to excite an explosion due to a rapid venting of built up pressure in the fuel tank during startup when a tail-pipe backfire occurs, not a known problem.
May or may not happen during startup, true.
If it were me, and I absolutely had to ditch the charcoal can, I'd cap the line and use a vented gas cap. That way the vapors are vented above the car where they can't be captured in underbody spaces.
Supreme Member
Quote:
Originally posted by kevinc
...says the guy who can't spell 'accelerated' but still feels qualified to give out advice...
With a functioning charcoal can, you will never, ever build enough pressure at the tank to open that vent. It's a safeguard to prevent the tank from popping in the event of a failure.
Oh no, not another spell checker. Get over it. You are right, it is a safeguard. One that operates exactly how I described. If it was a risk at all, it would have been put somewhere else on the car. Anyways, I thought you weren't, "interested in argueing beyond what you have posted?"Originally posted by kevinc
...says the guy who can't spell 'accelerated' but still feels qualified to give out advice...
With a functioning charcoal can, you will never, ever build enough pressure at the tank to open that vent. It's a safeguard to prevent the tank from popping in the event of a failure.
ok guys im lost. it seems to me we have moved past what i was asking to a fun argument. can someone with an LT1 please share with me what they did on thier car?
i wanna remove it if i can, because it isnt doing anything. if there is a way to hook it up and use it, ill do that.
im not gonna vent it under the car, if i do, i am going to put a filter inder the hood. if i do that? what filter do i need to use?
I got rid of it. Shouldn't be a problem to hook it up if you want to keep it. The solenoid on the canister is the same one used on the LT1 I believe, I think it was just mounted on the intake for the 4th gens.
so did u just put a filter on the line when u removed it?
no filter. not even real sure what we did with the line now its been so long since we did it.
Member
I don't have an LT1, but I did get rid of my charcoal canister. I just poked a couple of holes in my non-vented gas cap. Don't drill holes all the way through it, just puncture the diaphragm from the inside.

Member
Just my opinion but why wouldn’t you just keep the charcoal canister? It doesn’t cause any performance hindrance and keeps the fuel system closed loop, is safer, will allow you to pass any smog test and keeps the air cleaner. If you have the LT1 set up you can mount the canister out of site as the canisters are designed to be mounted in the rear of the car if cosmetics are an issue. Is there a flaw in my thinking?
Supreme Member
Quote:
Originally posted by David Petersen
Just my opinion but why wouldn’t you just keep the charcoal canister? Is there a flaw in my thinking?
Only one flaw in your thinking...you're assuming everyone has common sense.Originally posted by David Petersen
Just my opinion but why wouldn’t you just keep the charcoal canister? Is there a flaw in my thinking?
well, im under the idea that if it isnt doing anything i dont want it there, i could move my air filter over there and make my own cold air setup. that was the idea anyway..the canister isnt wired in, and the vacum line that is sposed to go to the motor isnt goin anywhere..so my question was:
a: how do i hook it up
or
b: how do i safely remove it?
a: how do i hook it up
or
b: how do i safely remove it?
Quote:
Originally posted by kevinc
Only one flaw in your thinking...you're assuming everyone has common sense.
Originally posted by kevinc
Only one flaw in your thinking...you're assuming everyone has common sense.
Or...we do have common sense, and realize its not that big of a deal.
Supreme Member
Quote:
Originally posted by TexasLT1
Or...we do have common sense, and realize its not that big of a deal.
You've evidently never experienced a gas explosion firsthand.Originally posted by TexasLT1
Or...we do have common sense, and realize its not that big of a deal.
When you do, you'll have more respect for fuel vapor (if you live).
(kevinc signs off this thread)
Junior Member
I know this is an old thread, but I have to put in my .02 cents. I was at the track yesterday and had fuel slosh out my vented cap during hard cornering. It created a siphonage effect that ran down the side of the car and inside the car on the fuel filler hose down to the exhaust. It ignited a huge ball of flame either during a downshift or when I hit the rev limiter. Scared my buddy that was in hot pursuit. But no major problems other than that. I plugged the cap and no longer had the issues.
Junior Member
Amazingly I found a video of my car at the track from someone behind me when the gas ignited.
Notice the fuel spill around the corner. Lots of mulla on the track
Glad no one was hurt. Good to keep the fuel system a closed system!
http://www.trackvisions.com/track2.wmv
Notice the fuel spill around the corner. Lots of mulla on the track
Glad no one was hurt. Good to keep the fuel system a closed system!http://www.trackvisions.com/track2.wmv
Member
nice video but listening to that whining honda makes me want to barf

Supreme Member
Quote:
(kevinc signs off this thread)
Originally Posted by kevinc
(kevinc signs off this thread)
The best contribution he has made to this thread yet!
