C3 Tech/Performance V8 Technical Info, Internal Engine, External Engine, Basic Tech and Maintenance for the C3 Corvette
Sponsored by:
Sponsored by:

Emissions???

Thread Tools
 
Search this Thread
 
Old May 13, 2015 | 03:59 PM
  #1  
Aggitated Monkey's Avatar
Aggitated Monkey
Thread Starter
Drifting
10 Year Member
 
Joined: Sep 2007
Posts: 1,572
Likes: 51
From: Wichita Kansas
Default Emissions???

With the install of my 383 i have removed the vapor canistor. I have concern with fire when those canisters fill with gas over the years and i dont think it cool to leave the tubue open for raw vapor to excape.

My question is what to do about the left over vent tube running from the engine bay to the tank? I was think about disconnecting it at the fuel tank and letting it just vent. Any thought on this? If left connected to the fuel tank what is the safe approach to the open tube in the engine bay?

I guess I need to think about the return line from the pump to the tank also.

Last edited by Aggitated Monkey; May 13, 2015 at 04:01 PM.
Reply
Old May 13, 2015 | 04:12 PM
  #2  
Alan 71's Avatar
Alan 71
Team Owner
15 Year Member
Active Streak: 120 Days
Community Influencer
Top Answer: 5
 
Joined: Sep 2006
Posts: 31,172
Likes: 4,249
From: Westminster Maryland
Default

Hi AM,
I didn't realize the vapor canister filled with gasoline over the years.
I thought the vapor separator mounted on the side of the tank prevented anything but fumes from being drawn into the line and then forward into the canister.
Regards,
Alan
Reply
Old May 13, 2015 | 05:39 PM
  #3  
Griff2002's Avatar
Griff2002
Pro
25 Year Member
Liked
Loved
Community Favorite
 
Joined: Jan 2001
Posts: 511
Likes: 66
From: Timnath, CO
Default

I agree with Alan that you should not get liquid in that line. However I think I've read that some people have had problems with malfunctioning V/L separators. I personally like the canister as it helps reduce fumes in my garage, which could also prove dangerous. I don't think you should vent to the atmosphere - I would cap the vent if you don't use the canister.

As an aside, it seems the carbon loses it's ability to desorb the gasoline over time. When I changed my carbon out, the gas smell was very strong. I put a match to a small sample of it, and this is what happened:

Reply
Old May 13, 2015 | 06:39 PM
  #4  
cardo0's Avatar
cardo0
Le Mans Master
20 Year Member
 
Joined: Oct 2002
Posts: 7,098
Likes: 378
From: Las Vegas - Just stop perpetuating myths please.
Default

As it is now u have an intake manifold leak and need to plug the flex hose to carb base. Next u need to find a method of venting the tank as the line from tank to charcoal canister is what vented the tank. As that remains open now u have gasoline vapors that flow past the little float check valve near the tank to the removed CC. So raw gas vapor is exiting near your exh manifolds. But if u plug it then the only way the tank relieves pressure is through the gas cap. Yes a gas cap will fart to relieve pressure. Also a gas cap will vent the other way when tank vacuum is greated when fuel is used up. But using the gas cap is not the way to control tank pressure as it is a safety valve not a regulator and will be problematic giving u gost problems with fuel supply.

Option is use a early years "vented" vap that is only a gas cap w/o a gasket and let your garage fill up with fumes. Or u can restore your CC and just replace the charcoal filter at normal intervals as in your owners manual. Yes Fram still makes and sells these filters.

Any questions?
Reply
Old May 13, 2015 | 10:31 PM
  #5  
Aggitated Monkey's Avatar
Aggitated Monkey
Thread Starter
Drifting
10 Year Member
 
Joined: Sep 2007
Posts: 1,572
Likes: 51
From: Wichita Kansas
Default

Ok thanks for the input. I think I will put the canister back in and let it do its job. I'm in the clean a paint portion of the build. Once I re assemble the under carrage and install the new engine and trans I will re connect the can. The original connection was to the A Jet. I'm running a Quick Fuel SS 750 CFM on top of the 383 stroker. Am I correct to think I can source any vacuums port for the vapor canister?
Reply
Old May 13, 2015 | 11:05 PM
  #6  
cardo0's Avatar
cardo0
Le Mans Master
20 Year Member
 
Joined: Oct 2002
Posts: 7,098
Likes: 378
From: Las Vegas - Just stop perpetuating myths please.
Default

No! The carb vacuum connection used/needed is what they call a ported vacuum that is connected to the venturi above the throttle plates. The reason is if the intake vacuum - which is highest at idle - takes in the stored vapor at start-up or even idle it may well stall from an over rich condition. I think this was discovered during the canisters development or what/when ever. But u need a port above the throttle plates.

What i use to identify ports is a thin solid wire to probe through the connection nipple and see where it enters the carb/venturi.

Good luck.
Reply
Old May 14, 2015 | 06:44 AM
  #7  
Alan 71's Avatar
Alan 71
Team Owner
15 Year Member
Active Streak: 120 Days
Community Influencer
Top Answer: 5
 
Joined: Sep 2006
Posts: 31,172
Likes: 4,249
From: Westminster Maryland
Default

Hi ag,
The instructions on the top of the canister indicate what the proper connections are.
Regards,
Alan



Reply
Old May 14, 2015 | 03:40 PM
  #8  
Aggitated Monkey's Avatar
Aggitated Monkey
Thread Starter
Drifting
10 Year Member
 
Joined: Sep 2007
Posts: 1,572
Likes: 51
From: Wichita Kansas
Default

Thank you all for the valuable information. The canister will go back in. Glade I asked.
Reply
Corvette Stories

The Best of Corvette for Corvette Enthusiasts

story-0

150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter

 Joe Kucinski
story-1

8 Coolest Corvette Pace Cars (and Replicas) of All Time

 Verdad Gallardo
story-2

Top 10 Corvette Engines RANKED by Peak Torque (70+ Years of Muscle!)

 Joe Kucinski
story-3

Corvette ZR1X Will Be Pacing the Indy 500, And Could Probably Race, Too!

 Verdad Gallardo
story-4

Top 10 Corvettes Coming to Mecum Indy 2026!

 Brett Foote
story-5

Top 10 C9 Corvette MUST-HAVES to Fix These C8 Generation Flaws!

 Michael S. Palmer
story-6

10 Revolutionary 'Corvette Firsts' Most People Don't Know

 Joe Kucinski
story-7

5 Reasons to Upgrade to an LS6-Powered Corvette; 5 Reasons to Stay LT2

 Michael S. Palmer
story-8

2027 Corvette vs The World: Every C8 vs Its Closest Competitor

 Joe Kucinski
story-9

10 Most Common Corvette Problems of the Last 20 Years!

 Joe Kucinski
Old May 14, 2015 | 04:44 PM
  #9  
ddawson's Avatar
ddawson
Le Mans Master
25 Year Member
Liked
Loved
Community Favorite
 
Joined: Mar 2001
Posts: 5,738
Likes: 644
From: Lincoln, CA
Default

The carbon acts as sponge. It has a high absorption rate. So after parking it will absorb the fumes and when the car is running get sucked back in.

Changing the media will help as it does break down over time and have less service area.

I'm big into Reef tanks. Same concept but we have to throw it out once it's exhausted and no longer absorbing. You don't want it leaching back into the water.
Reply

Get notified of new replies

To Emissions???





All times are GMT -4. The time now is 03:16 PM.

story-0
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter

Slideshow: From C1 to C8 we compare every Corvette generation by the numbers.

By Joe Kucinski | 2026-05-12 16:54:12


VIEW MORE
story-1
8 Coolest Corvette Pace Cars (and Replicas) of All Time

Slideshow: Some Corvette pace cars became collectible legends, while others perfectly captured the look and attitude of their era.

By Verdad Gallardo | 2026-05-11 09:50:51


VIEW MORE
story-2
Top 10 Corvette Engines RANKED by Peak Torque (70+ Years of Muscle!)

Slideshow: Ranking the top 10 Corvette engines by torque output.

By Joe Kucinski | 2026-05-05 11:58:09


VIEW MORE
story-3
Corvette ZR1X Will Be Pacing the Indy 500, And Could Probably Race, Too!

Slideshow: A Corvette pace car nearly matching IndyCar speeds sounds exaggerated, until you look at the numbers.

By Verdad Gallardo | 2026-05-04 20:03:36


VIEW MORE
story-4
Top 10 Corvettes Coming to Mecum Indy 2026!

Among a rather large group of them.

By Brett Foote | 2026-05-04 13:56:44


VIEW MORE
story-5
Top 10 C9 Corvette MUST-HAVES to Fix These C8 Generation Flaws!

Slideshow: the top 10 things Corvette owners want in the C9 Corvette

By Michael S. Palmer | 2026-04-30 12:41:15


VIEW MORE
story-6
10 Revolutionary 'Corvette Firsts' Most People Don't Know

Slideshow: 10 Important Corvette 'firsts' that every fan should know.

By Joe Kucinski | 2026-04-29 17:02:16


VIEW MORE
story-7
5 Reasons to Upgrade to an LS6-Powered Corvette; 5 Reasons to Stay LT2

Slideshow: Should you buy a 2020-2026 Corvette or wait for 2027?

By Michael S. Palmer | 2026-04-22 10:08:58


VIEW MORE
story-8
2027 Corvette vs The World: Every C8 vs Its Closest Competitor

Slideshow: 2027 Corvette lineup vs the world.

By Joe Kucinski | 2026-04-24 16:12:42


VIEW MORE
story-9
10 Most Common Corvette Problems of the Last 20 Years!

Slideshow: 10 major Corvette problems from the last 20 years.

By Joe Kucinski | 2026-04-14 16:37:05


VIEW MORE