First off, Mods feel free to sticky. Actually PLEASE sticky, because from personal experience in looking around, this would have helped me decide to vent or not!

You may not agree with what I say, but its only an opinion, and if you present something respectfully, I won't have a problem with editing it in. I know this may be flamed because I'm 18, or I don't have many posts, and I know I don't know it all but I've done a lot of research so I'm presenting what I have to end the ultimate question: Can you vent a BOV on stock or close to stock Audis?

The question of venting BOVs comes up a lot and there are always answers, but few account of real performance, as well as drive-ability. So I am posting this as an exact detail of my experiences. I at first was the typical teen who wanted the JDM tyte pshhht sound, and yes, you do get it, and yeah its major cool. Keep reading though before you slide your hand open in a frenzy to yank the recirculation tube off. As with all, YMMV

My Car: A STOCK Audi a4 1.8t with a tiptronic. I believe that people have a gripe when someone posts, because “well your car isn't stock so it handles venting differently”. So in this test, ill have a stock car, as well as a stock DV. The DV will be run STOCK, no changes, except venting. When I get a new DV, ill update the post with my findings.

I first drove the car like I normally would, letting the fluids warm up to operating temp. I then went and unplugged the DV at the rubber hose and capped the intake end. The car started up as usual but after about 3 seconds it began idling terribly. The car never stalled, but for maybe 2 minutes it stumbled and the rpms varied from 400-1400. Then within a matter of seconds, it settled down and was right at 850 as usual. Tooling around the neighborhood at normal speeds and loads was normal, and when I put it in tip and treated it like a manual (letting off the gas while shifting) it was fine as well, although I did get a slight delay getting back on the gas (or maybe it was just me) either way, it was very minor. I eased into about %25 throttle, spooled a bit and let off. There it was, the oh so sweet pshhht sound. More gas, more sound. I'm not going to lie, I LOVED it. So I left it in tip mode and drove around town. Normal drivability, (which means for me driving with the acceleration of a soccer mom) was fine, and light applications of boost were good.

The problems arose the first time I got into serious boost.

You know those times when your at a red light, your the only car, and you see the traffic from the previous light before you? So you know the lights about to be green. Well my thought was “I've got my handy dandy Audi turbo with a Tiptronic, ill be at 50 before they realize they didn't have to slow down for me mwahahaha (slides shifter to Tip mode.) Light goes green, and I casually roll to 15, then floor it. Well, to say the least, the traffic caught up. Initial spool was just as good as usual, then the SWSSSSSSS from the k03 became a swsssss (but in 2 point font). Very little boost at all. Still got the BOV sound, but it was less aggressive. After shifting into 2nd (remember I let off the gas while shifting), I got some definite hesitation when getting back into it. Well along my drive, I run into Captain JDM driving his green accord, with the not painted yet body kit, and nice big muffler for 50 hp. He puts it into N and violently revs it attempting to make me race. Now if I would have raced him, I am assuming this is now it would have gone

Light turns green. He neutral drops into what I'm assuming was L, little wheelspin and laughter ensue. I'm in tip/1st gear so I WOT. Even through 1st. I let up and “shift”, car stumbles he pulls about ¼ a car, but I still kill him through 2nd... and 3rd.....

I declare this drivable and decide to continue testing throughout the week. Monday and Tuesday are fine, and it starts going around school, that there's some way cool senior with his awesome turbo Audi and its sooooo omg fast. My car friends laugh at the general school population for being ricers.

Hypothetical races:
Wins vs:
90s Accord
2003 Civics and under
Jeep
Jetta 4 banger
GTI 4 banger
Saturn something
Some mini truck

Lose vs:
Jetta 1.8t*
08 Toyota Tacoma prerunner ^
Cobalt SS ^and turbo
BMW 1 series
Early 00 mustang ^
Corolla S*

Basically ties vs:
Integra I/H/E *
prelude *
Hyundai Elantra (so sad) *

The * denotes a car that I previously was able to beat, and the ^ was a tie normally
except the mustang, it pulled on me past 3rd

So its Friday, and everyone's being stupid in the parking lot, I start my car, let it idle down like normal, then WOT down the parking lot, BOV happens, I go to neutral to slow down and As the rpms drop from 5k, I sort of notice that the exhaust/general tone the car makes sounds off. As the car hits 1k rpm, the rpms keep dropping just as fast, straight to 0. Absolutely NO attempt to idle, just flat. So I cycle the ignition, and the car fires right up, gets to 1200 for a split second and dies just as fast. Pop the hood, all the hoses are in order, and the DV cap is where it should be. 3rd start and I coax it up to 2k where it seems to be ok, but still so sustained idle. So I limp it home, and by the time I get there, it idles again. So it was DUMPING fuel, because it was cold, and there was a chunk of air being miscalculated.

MPGs: TOTAL CRAP. I got about 150 miles out of ¾ a tank with light to moderate driving %75 of the time. Saturday I put everything back where it should be, and reset the ECU. It felt like a completely different car! Almost like I chipped it or something...

Summary: venting is %80 drivable, just don't WOT when warming up, or have fun with stalling for 20 minutes. You will lose about 30 hp id guess considering what I won/lost to.

 

Oh yeah, this was over a week timespan and i didn't get any backfires...

 

i feel stupider for reading this. just go buy a forge splitter.

 

This might be one of the funnier things ive read lately... not flaming you or anything, but what was the point of all this again? And how did you come up with these "hypothetical races"?

 

im gonna guess he played need for speed on his xbox and used those results

 

It was a joke. These were real races, I just didnt wan't to flat out say I riced my car for week... Like I said, I'm about to buy a decent dv, (not a splitter, because there's still lost air, so the car wont be running at %100). I only posted this because it might help someone in their decision.

 

Not completly true...you can put the. Plug instead of the horn ad make it completly recirculating....

 

I just figured out that my DV is cracked. I'm actually glad I read your post because that confirms why my engine would occasionally turn off after getting on the throttle a few times. Basically, there should be a sticky saying that for our cars, DV's = Good, BOV's = Bad.

 

Ok thanks, I didn't know that. Would you suggest a Forge 007? Or is there a better alternative?

I'm glad I could help, thats the only reason I made this post, to help someone.
If someone thinks its a good idea for a sticky, I'd be ok with writing a FAQ about DV/BOV.

EDIT: This also was part of a paper I had for english, so I figured why not post it and see if it hepls anyone. Glad it did.

 

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