another venting question

[GreddySpyder]

I just have a simple question about venting my Greddy Type S BOV to the atmosphere. Everybody says that you will get better gas mileage venting to the intake tube, so i put the hose on to vent it to the intake, and my gas mileage has actually dropped. I don't understand, somebody please educate me here.

 

[BatmanGSX]

 

[GreddySpyder]

Originally posted by BatmanGSX

I realize that this post is probably a repeat or that I may not have given you what you consider to be enough info. The throwing up face is quite possibly the most retarded response you could have given, given the time you took to respond you could have at least said something. All I'm asking is if anybody else has experienced the same thing... losing gas mileage after venting back to the intake?

 

[toshi128]

you should search for it on this site, since this has been a popular subject for a long time.

No, i didn't lose any mileage from venting back to the intake. i actually gained about 2 + miles per gallon from it.

 

[madmax]

That just seems odd that you would lose fuel efficiency venting to the intake. Venting to the atmosphere is known to create a rich condition, which uses more fuel. I don't have the answer, but I don't thiink it has anything to do with your BOV, there is another factor thats causing your problem.

 

[BatmanGSX]

Originally posted by GreddySpyder


I realize that this post is probably a repeat or that I may not have given you what you consider to be enough info. The throwing up face is quite possibly the most retarded response you could have given, given the time you took to respond you could have at least said something. All I'm asking is if anybody else has experienced the same thing... losing gas mileage after venting back to the intake?

 

[asian312]

BatmanGSX, u really hate venting to atmosphere, dont ya?

Anyways, I have that dreaded Apexi one that can only vent to atmosphere, but I do have a AFC to control it. Never really noticed a really large, if any at all, change in A/F. But b4 this goes into a venting post, I manage roughly 350-400 miles to a tank. That's in Houston traffic and on 93 oct.

 

[BatmanGSX]

Originally posted by asian312
BatmanGSX, u really hate venting to atmosphere, dont ya?

Anyways, I have that dreaded Apexi one that can only vent to atmosphere, but I do have a AFC to control it. Never really noticed a really large, if any at all, change in A/F. But b4 this goes into a venting post, I manage roughly 350-400 miles to a tank. That's in Houston traffic and on 93 oct.

 

[madmax]

Originally posted by asian312
BatmanGSX, u really hate venting to atmosphere, dont ya?

Anyways, I have that dreaded Apexi one that can only vent to atmosphere, but I do have a AFC to control it. Never really noticed a really large, if any at all, change in A/F. But b4 this goes into a venting post, I manage roughly 350-400 miles to a tank. That's in Houston traffic and on 93 oct.

I find that hard to believe. Unless, you drive so softly not to achieve any boost. I get 250 in the city. I've spoken and read of many others getting about 250 in the city. i get about 400 when i drive on the highway when going home.

 

[OneSickTSi]

Before asking a stupid question like that you should have searched it from the site. but anyway, the reason why you lose gas mileage when venting in to open atmosphere without the APEX'i AFC or the HKS, is because when you shift, the ECU reads how much air is going through the motor and changes the fuel settings which make you run super rich and when running rich you lose more gasoline, therfore you are losing gas mileage left and right, a suggestion would be is to get the AFC, get it tuned properly then vent it, or just suffer losing the gas mileage and watch the ladies turn the heads and say "Oh My" when the loud "Swoosh" comes from under your hood, only problem with that, is that you don't get ladies on your tip everytime that happens. take it easy man, peace
Chris

 

[toshi128]

Originally posted by OneSickTSi
Before asking a stupid question like that you should have searched it from the site. but anyway, the reason why you lose gas mileage when venting in to open atmosphere without the APEX'i AFC or the HKS, is because when you shift, the ECU reads how much air is going through the motor and changes the fuel settings which make you run super rich and when running rich you lose more gasoline, therfore you are losing gas mileage left and right, a suggestion would be is to get the AFC, get it tuned properly then vent it, or just suffer losing the gas mileage and watch the ladies turn the heads and say "Oh My" when the loud "Swoosh" comes from under your hood, only problem with that, is that you don't get ladies on your tip everytime that happens. take it easy man, peace
Chris

I thought you can't over take the venting to atmosphere problem with AFC, unless if you get VPC so you can get rid of your mas, then you don't have to worry about venting...

am i wrong?????

 

[dikbutkiss]

unless im a confused idiot, im pretty sure that when venting to the atmosphere or recirculating the same amount of fuel is sprayed because either way, the same amount of air is measured and the ecu sprays the same amount of feul for the same amount of air. the only difference is you will run rich when you blow off to the atmosphere because the air that you blow off is already had some fuel with its name on it.

so why would you get better gas milage with the recirc?

 

[toshi128]

Originally posted by dikbutkiss
unless im a confused idiot, im pretty sure that when venting to the atmosphere or recirculating the same amount of fuel is sprayed because either way, the same amount of air is measured and the ecu sprays the same amount of feul for the same amount of air. the only difference is you will run rich when you blow off to the atmosphere because the air that you blow off is already had some fuel with its name on it.

so why would you get better gas milage with the recirc?

our mas (located right after the air filter) reads the amount of air sucked in by the turbo, then the ecu measures the amount of air then gives the appropriate amount of fuel to support. However, if the air is lost through the process (venting to atmophere), the ecu still thinks that the air is giong to the engine, so it gives the extra fuel. This happens when you let go off the gas pedal. This may not be extra fuel, however, the car should be moving with the fuel that was lost. So, if you vent back into the intake, you can reuse the air. So, I *think* the reason why i get better gas mileage is because of reusing the air from my bov.

I appology if I was wrong or not clear enough.

 

[talonted_one]

it looks to me that whoever is getting better mileage when venting is running lean.


am i wrong?

 

[LandoAWD]

 

[Nick 4g63]

Originally posted by LandoAWD

vent: run rich and stumble/sputter everywhere n MPG goes to #@%#@%#@%#@%

recirculate: the whoosh sound isnt as near as loud, MPG restored, no more stumbles. end of argument for that

i agree with the venting helping MPGs out being a serious fuel problem that needs to be looked into. Buy urself an EGT gauge n see whats going on there.

 

[ProjectGSX]

I did not notice any MPG changes when going from intake to atmosphere.

I have not seen anyone state factual evidence indicating exactly how rich you run when venting to atmosphere or for how long. No one knows. In my experience, it is negligable.

 

[freakaccident]

Doesn't the AFC get adjusted to the point where the stock ECU can't compensate anymore? Who really cares anyway? Whatever your reason for venting or not venting is it's your car so do what you want. If you don't have any good info then STFU!

 

[BatmanGSX]

I LIKE ANAL

 

[onegee]

okay...maybe the ecu got adjusted to u venting or something..now that ur recirc. it has to readjust again....

i frankly have no damn clue and thats my best guess...i was venting to atmos. with my hks with no problems...i had a SMALL decrease in mpg but im recirc. again and i get 330miles/full tank give or take a few..now the only performance gain in recirc. i think is keeping the turbo spooled a bit more? can someone verify this? ....well yeah, umm...k bye ...haha

 

[GreddySpyder]

To onesicktsi and freakaccident, it doesn't even look like you read the orginal question. To all those people that just say "use the search", i DID use the search before posting this question, but everything i found said that gas mileage should go UP after venting to the air intake. All I am looking for is some educated theories as to what could cause gas mileage to go down after doing this when everybody else seems to gain gas mileage. I'm getting pretty crappy gas mileage either way, between 200-230 miles between fill ups, which usually comes out to about 18-20mpg when i figure it up. I'm sure some of this is contributed to my aggressive driving habits and running 15 psi daily, but i still wouldn't think i should be using this much fuel on the stock turbo and fuel components. One thing i have noticed since buying this car is that i never hear the "hiss" whenever i take off my fuel cap to fill up, that means that I could have some fuel vaporizing past the cap, right?