[Clipse3GT]

As many of you know I am running a Haltech E8 EMS, and plenty of other goodies. Anyways, since the EVAP system is eleminated along with the valve, solenoid, EGR pipe etc...

Now since the gas tank uses, those parts as part of its emission system. You have basically 3 lines running from the tank. A fuel feed line, a fuel return line, and a fuel fume/gas line. Now considering that you dont have this EVAP system anymore. And the fume line line is blocked off, you can assume that during warm weather those hot gases will build up in the gas tank and can cause vapor lock in the fuel feed lines an cause the car to sputter.

Now if you would run a line with a one way valve from the fume/gas line that runs into the engine compartment, that used to be part of the EVAP system, then let it run to the intake manifold. (Think of the way the brake booster is constructed.) Would you expect it work similarly to that of the old EVAP system, that under vacuum it would suck those fumes out and then under boost the valve would close, and boost would not sneak into the gas tank?

Discuss.

 

[Chief Brody]

Do you mean the evaporate emmissions control (EVAP) system, instead of EGR?

 

[callmeebryan]

Vapor lock is very rare in fuel injected cars, especially ones with high fuel pressures. Vapor lock was a problem in carberated cars in the past when negative pressure was used to pull fuel from the tank.

especially with stainless steel lines, your lines will be protected from extreme heat and will hold that fuel pressure very well....

I would be more worried about running out of fuel than sucking in fuel vapor.... thats why i never run my car below 1/4 tank of gas.

 

[PharmEcis]

Do you mean the evaporate emmissions control (EVAP) system, instead of EGR?

+1

EGR = Exhaust Gas Recirculation
EVAP is for the third line to the tank.

 

[Clipse3GT]

+1

EGR = Exhaust Gas Recirculation
EVAP is for the third line to the tank.

Right :wiggle:

 

[Clipse3GT]

SO everyone is clueless on this?

 

[PharmEcis]

Including you. :fawk:

 

[FlashBlueRS]

Now if you would run a line with a one way valve from the fume/gas line that runs into the engine compartment, that used to be part of the EVAP system, then let it run to the intake manifold. (Think of the way the brake booster is constructed.) Would you expect it work similarly to that of the old EVAP system, that under vacuum it would suck those fumes out and then under boost the valve would close, and boost would not sneak into the gas tank?

That is how the evo's are setup. They have a small check valve to prevent boost from entering the gas tank.

 

[repforenzo]

As many of you know I am running a Haltech E8 EMS, and plenty of other goodies. Anyways, since the EVAP system is eleminated along with the valve, solenoid, EGR pipe etc...

Now since the gas tank uses, those parts as part of its emission system. You have basically 3 lines running from the tank. A fuel feed line, a fuel return line, and a fuel fume/gas line. Now considering that you dont have this EVAP system anymore. And the fume line line is blocked off, you can assume that during warm weather those hot gases will build up in the gas tank and can cause vapor lock in the fuel feed lines an cause the car to sputter.

Now if you would run a line with a one way valve from the fume/gas line that runs into the engine compartment, that used to be part of the EVAP system, then let it run to the intake manifold. (Think of the way the brake booster is constructed.) Would you expect it work similarly to that of the old EVAP system, that under vacuum it would suck those fumes out and then under boost the valve would close, and boost would not sneak into the gas tank?

Discuss.

I read up on it a bit in 17-91 of the manual. According to that chapter, the EVAP purge solenoid engages a specific times. Idle surprisingly, is not one of those times. My impression is you don't want to implement a strong, constant vacuum source going from the tank to the intake. Is there such a thing as a vacuum regulator? If so, and you can set it to like, 2-4 in/hg, that might be enough for your needs.


In order: tank===>Vac. Reg.=====>check valve====>intake. That's how I would try to tackle it.

 

[FlashBlueRS]

the evap solenoid only allows vacuum while cruising with less than 2/3 of the tank full.

 

[repforenzo]

the evap solenoid only allows vacuum while cruising with less than 2/3 of the tank full.

Then just keep the tank full.

 

[Bitter]

take a look at how they did evap on older cars which were carbed with an intank electric pump or obd1 cars which have evap systems.

 

[Clipse3GT]

Well either way, what about just putting on a breather filter on the end of the tube. Sometime this year I am putting in a new fuel cell and pump, so it won't matter as much.

I can see what you mean running a constant vaccum on the tank, high likely hood of sucking fuel when the tank is full.

 

[Bitter]

well you'll want to put that tube somewhere else away from things that can catch it afire. also when the tank cools it'll suck in moist air from outside. def need a check valve!

 

[Clipse3GT]

well you'll want to put that tube somewhere else away from things that can catch it afire. also when the tank cools it'll suck in moist air from outside. def need a check valve!

So you think that I should run:

Tank---->Hose---->Check Valve----->Hose----->Breather Filter

OR

Tank---->Hose---->Check Valve----->Hose----->Intake Manifold

 

[Bitter]

well ideally it'd should be stock or controlled somehow, but since that probably wont happen the former is preferable from an operational standpoint. however the gasoline fumes seeping from the car are a fire hazard in my mind.

 

[repforenzo]

So you think that I should run:

Tank---->Hose---->Check Valve----->Hose----->Breather Filter

OR

Tank---->Hose---->Check Valve----->Hose----->Intake Manifold

Because of the high evaporation rate of gasoline, Bitter is right about being a possible fire hazard.

The second option is also flawed because of the high vacuum issue.

It might be best to block it off.

 

[Clipse3GT]

Because of the high evaporation rate of gasoline, Bitter is right about being a possible fire hazard.

The second option is also flawed because of the high vacuum issue.

It might be best to block it off.

Well that's what I have right now. Its just blocked off with a vacuum cap. I was just thinking of a possible solution for this, but it seems that neither way is really good.

 

[NAPALM]

My ECU actually has the outputs and control for the EVAP but I dont use it.
I have the hoses hooked up like stock, but the purge valve is electrically disconnected and all of the outputs in the EMS cal are disabled.

I suppose I could set it up. :dunno: Never really thought about it too much.

However, I definately dont think that connecting it to unregulated (no electronically controlled purge solenoid) vacuum is a good idea.

 

[zeeshan]

its simple to set this up, get under the car, you will see the evap hose. vent it to the atmosphere away from any hot parts right there. this is the same thing you have to do with your fuel cell when you get one.


don't plug it, it will cause vacuum to form from the displacement of fuel. this vacuum in your fuel tank is usually enough to own some seals and deform the stock plastic tank.