DSMLink... Vent or Recirculate?

[usmc0651dns]

The only post I could really find was like 4 years old. If I am running DSMLink do I need to recirculate. I have the Greddy Type S and as far as I know my GSX should have a place to tap into the intake. Just bought it last night so not sure. Also not sure if my DSMLink is V 3 or not.

 

[snowborder714]

DSMlink does not give you a "yes or no" for venting.

If you are running a blow thru GM MAF setup (either ECMtuning's GM MAF cable or MAFT setup) or speed density (ECMlink v3 only - not available on v2.5) then you can vent properly. Otherwise you should be recirculating.

 

[jed344]

why vent it anyway i have a 1g bov recirculated and its still very loud with a intake just as loud as my buddys vented

 

[Achelea]

I would recirculate it personally. As Snowboarder pointed out, you should recirculate. The computer has already measured the air, if you vent it, you're losing metered air and running rich.

Kinda like paying for a hundred clams and dropping 13 on the way to the car.

 

[slowboy101]

when you have dsm link you can tune around the vented, thats what I did I have a GM MAF blow thru set up with a RFL BOV and its vented and I dont have a problem!

 

[belize1334]

It really comes down to whether you're metering the air before or after the BOV. If you meter after the BOV then it doesn't matter. That's why slowbody101 doesn't have an issue with his blow-through GM Maf. If you meter before the BOV then you're venting metered air, in which case you must recirculate it. Now, as a fix v3 gives you the option of capping the airflow value at lift off. This FORCES the ecu not to count air during lift and largely corrects for the issues that arise with an improperly vented BOV ... but that's a band-aid and is not the "correct" method.

 

[slowboy101]

Exactly ^^^ but GM maf blow thru can be spendy and you have to know what your doing when using it or you can mess things up

 

[usmc0651dns]

Thanks a lot guys. I'll just go ahead and grab a Dejon intake pipe with the recirculate fitting and set it up.

 

[JStrateger]

Blowing off to the atmosphere or recirculating into the intake is an age old question around here. It's been covered time and time again, pros and cons listed multiple times but what it boils down to is what your car is going to be used for. The performance enthusiasts will tell you that recirculation is the way to go.
When you run a vented blow off valve on a stock MAF setup with these cars the computer thinks more air is entering the combustion chamber than actually is, so it dumps in more fuel than is needed making a rich air fuel mixture. This is because your loosing metered air in the system every time the valve opens. Using a GM Mass Air Flower Sensor and a MAF translator box and placing the sensor AFTER the blow off valve in your system eliminates this problem and allows you to vent to the atmosphere with no issues.
Even though the majority of the time, vented blow off valves run on stock, low boost setups have such minuscule effects, it doesn't effect performance as much as some people lead you to believe, but is still frowned upon.

On the other hand, If your using your car to pick up girls.. they love the iconic woosh sound and you should vent to the atmosphere. Always dress to impress.

Her: "Whats that sound??"
You: "That means my cars fast."
Her: ", Take me now!"
You: NOM NOM NOM

 

[usmc0651dns]

I had an SRT-4 that blew off easier and quicker then most girls The sound really isn't as important to me as ling as you can hear that glorious turbo spool. Since I don't have a V3 Link and still use the 2G MAFS I'll stick to recirculating. Thanks for the info guys.

 

[Clinical]

yeah when I first got my car it had a Blitz SS vented despite running a 2g MAF.

I put on my type s, did a pull with it vented. Then recirculated it and the sound practically stayed the same.

Just get an aftermarket intake and there wont be much if any difference.

 

[JusMX141]

I put on my type s, did a pull with it vented. Then recirculated it and the sound practically stayed the same.

If you're running a high boost level, the valve is going to sound the same vented as it would recirculated. The air escaping the valve is ten times more audible at 25psi than it is at 10psi.

With that in mind....

• If your girlfriend is more impressed by the sound your blow off valve emits than how fast your car is, then your car is too slow.
  
  
• If you're spending $250 on a blow off valve just because it is louder than stock, you're wasting your money. The idea behind a better-performing valve is not the sound that it makes....and this may come as a shock to you- but how well it performs. Whether that means opening quicker, holding more boost, releasing more air, etc. In order to prompt the replacement of the stock valve, you must first reach the performance limit of the stock valve. Until then, you'd be better off putting the money toward supporting mods that will allow you to run more boost. You'll not only have a louder blow off valve, but your car will be faster, too.

 

[92AWDTalonTSI]

After reading all of this. I am no longer set on MAFT. I'll just keep mine how it is. Don't get me wrong. I love seeing people turn to look at whatever made the loud discharge. But in terms of stability and lack of funds. I'll keep that recirculation hose on.

 

[Calan]

...Using a GM Mass Air Flower Sensor and a MAF translator box and placing the sensor AFTER the blow off valve in your system eliminates this problem and allows you to vent to the atmosphere with no issues....

Good info in your post, but for the record...

Even though the unmetered air isn't an issue with a GM MAF in blow-through, you can still see some performance hits. I run the blow-through/MAFT configuration (when I'm not running SD), and I've ALWAYS had better performance with the BOV recirculated, no matter what the configuration or tune.

YMMV

 

[JayRolla]

Tuning is so much easier when running the maf infront of the turbo since this is where the ecu thinks its metering air. Not to mentions GM maf tunes wander and idle is rough sometimes. I like the mitsu evo maf or SD.

If you're running a high boost level, the valve is going to sound the same vented as it would recirculated. The air escaping the valve is ten times more audible at 25psi than it is at 10psi.

Remember its not the sound at WOT people want. They want that sound at the mid boost low rpm shifts to sound COOL!!

 

[CHAR-FT]

You: NOM NOM NOM

next time, make that sound to her

 

[Calan]

...They want that sound at the mid boost low rpm shifts to sound COOL!!

I'd rather hear the sound of all four tires breaking loose during a shift because the turbo is staying spooled up, rather than the "whoosh".

 

[JusMX141]

Remember its not the sound at WOT people want. They want that sound at the mid boost low rpm shifts to sound COOL!!

Right, but if you're running 22psi on an Evo III 16G you could blow off 22psi at around 4k or 7k and it will sound the same.

Damn ricers.

 

[ramsack]

how someone doesn't get sick of the constant blow-off sound when vented anytime they lift the gas boosting or not is beyond me. i can't tolerate it for more than a few times.

 

[usmc0651dns]

^^Agreed. I love hearing my SRT blow off when I was crushing Vtec's and Mustangs. However I always looked like a douche when I was trying to park at WalMart.

 

[HadesOmega]

why vent it anyway i have a 1g bov recirculated and its still very loud with a intake just as loud as my buddys vented

My RST is much louder than my GST both are using 1G BOV. I got an aftermarket intake pipe on the GST also. The GST is also boosting twice more boost.

But anyway you might as well just recirculate it, what are you going to do with the giant hole in the intake?

 

[floader]

I vented the BOV on my blow thu setup, only because it made the piping much more simple. I figured I could change if it got annoying, but being an automatic it does not seem too bad. Only makes noise when I lift real fast, if I just roll off the gas it makes no noise at all.

 

[ziggo0]

^^Agreed. I love hearing my SRT blow off when I was crushing Vtec's and Mustangs. However I always looked like a douche when I was trying to park at WalMart.

Or backing out of a parking spot blowing off 15 times, not trying either .

 

[JayRolla]

Right, but if you're running 22psi on an Evo III 16G you could blow off 22psi at around 4k or 7k and it will sound the same.

Damn ricers.

Actually mine is quite louder just running it vented. I like the 1g bov vented. Its about perfect since its not loud at all at low boost and has a good release at WOT.