Well, I'm back with proof. Running OEM Atmosphere BOV.

[forcefed86]

Well I was bashed and instantly had 100 people telling me I couldn't do it. Well I did, and it works just fine. Nothing crazy rich on the shifts and no poor idle or driveabilty issues.

Installed LC2 WB02. Went for a test run...

First run with the BOV setup OEM style. At 18lbs WOT I'm seeing around 9.5:1 AFR's. Lifting to shift (BOV active) AFR's jump to mid to high 12's. Then jump back up to 9.5:1.

Swapped in my brass check valve vented to atmosphere. PLugged open hole on intake tube. Same WOT AFR's same boost. At the shift AFR jumps up a bit less at 10.2-10.6, then drops back to mid 9's.

So there it is... do what U will with it. It's sure not washing down any cylinders running at 10:1. That is leaner than the factory map!

The factory AFR targets are as follows.

Also for what it's worth I've done the "dodge garage" MOD to the BOV. If anything this probably slows down the BOV, but thought I'd mention it.

Simple brass check valve installed. I've since painted everything black. But this pic shows the valve assy better.

 

[MidShipCivic]

If recirculating is SUCH a MASSIVE improvement over venting. Then why do none of the fastest DSM's recirculate? For that matter why do none of the quickest 1/4 mile cars recirculate? In this type of application a thousanth of a second could be the difference between winning and losing. Don't you think if recirculating BOV air netted any type of gain they would do it?

IMO for my purposes it's all hype.

The fastest DSM don't have a stock ecu or alter their perfect system to whoosh noises ... hell some of them don't even lift off of the throttle the entire run.

 

[nytescion]

Once again, why post on something you don't understand. You don't have a clue. It's not that much air people! I'm not running rich because the valve is closed during normal driving. And if you'd read the damn first paragraph of this post you'd see exactly what the mixture is doing under boost.

Your wrong, end of story....

IMO for my purposes it's all hype.

Apparently you're confused or missed something somewhere. We understand that at idle/cruise the check valve is closed. Now when you're boosting and you go to shift gears the air that is normally recirculated through the intake is vented. What they're saying it the ecu is already compensating (adding fuel) for this air because it's been metered already. So for that second or two when your throttle plate slams shut you're running rich. Now if you look at your wideband and it says lean during this shift then you're obviously sucking in air somewhere. We KNOW it's not the bov because air is rushing out of there.

However i do agree that if this is fine for you how the car is running. Then to hell with what I or anyone else says, do you. I vented mine with a 2gmas for the longest and i didn't give a damn what anyone said cause it was my car not theirs.

 

[spyderturbo007]

This thread makes me want to cry.

I applaud the time you took to obtain these results, but all it's done is reaffirm what we have been saying since day one. The DSM ECU expects certain conditions, such as a recirculated BOV. It assumes that previously metered air will be recirculated back into the intake post MAS and uses this assumption in its fuel delivery calculation.

By removing this metered air, you are altering the AFR. This has repercussions, such as fouled plugs, increased EGT's, unnecessary unburnt fuel entering the cat, etc. It's your car and you are more than welcome to do with it as you please, but it was designed that way for a reason. If you really want a louder BOV, why not just switch to DSMLink and run a SD setup?

 

[buryurfear14]

This thread makes me want to cry.

I applaud the time you took to obtain these results, but all it's done is reaffirm what we have been saying since day one. The DSM ECU expects certain conditions, such as a recirculated BOV. It assumes that previously metered air will be recirculated back into the intake post MAS and uses this assumption in its fuel delivery calculation.

By removing this metered air, you are altering the AFR. This has repercussions, such as fouled plugs, increased EGT's, unnecessary unburnt fuel entering the cat, etc. It's your car and you are more than welcome to do with it as you please, but it was designed that way for a reason. If you really want a louder BOV, why not just switch to DSMLink and run a SD setup?

With that said...

/thread

If you post again, I will maliciously come to your house and recirculate your BOV, with force and without consent.

 

[habitatguy187]

This thread makes me want to cry.

I applaud the time you took to obtain these results, but all it's done is reaffirm what we have been saying since day one. The DSM ECU expects certain conditions, such as a recirculated BOV. It assumes that previously metered air will be recirculated back into the intake post MAS and uses this assumption in its fuel delivery calculation.

By removing this metered air, you are altering the AFR. This has repercussions, such as fouled plugs, LOWERED EGT's, unnecessary unburnt fuel entering the cat, etc. It's your car and you are more than welcome to do with it as you please, but it was designed that way for a reason. If you really want a louder BOV, why not just switch to DSMLink and run a SD setup?

Fixed

 

[dsm-onster]

Exploding gas in the exhaust manifold certainly RAISES EGTs

OP in addition to the check valve on the original BOV, you need another BOV at the intake pipe that senses sudden vacuum and opens to let air in when the original BOV is venting in between shifts . . . Now we see why Mitsu elected to do the more affordable less complicated recirculated setup.

 

[96eclipzGsT]

I don't get what the check valve is for. You put it in one direction the BOV is not working, and the other direction, air just moves straight through it. Wouldn't that be pointless? My bet is he has the check valve in where it is blocking the BOV from working.

 

[dsm-onster]

No when he's on boost the bypass valve is closed and keeps boost in the UICP. When his throttle closes suddenly the bypass valve opens and that pressureized air flows through the check valve to the atmosphere.

When he's cruising/idle, there's enough vacuum to open the bypass valve. But air can't be sucked in by the motor because the check valve prevents it.

He's still blowing a whole lot of air, that his turbo spent alot of energy getting into the UICP right out in the air, AFTER it has already been metered. I'd rather direct that air into the compressor helix to give the energy back to the compressor at least helping to stay spinning faster for longer. Rotational inertia is a b!tch

 

[96eclipzGsT]

No when he's on boost the bypass valve is closed and keeps boost in the UICP. When his throttle closes suddenly the bypass valve opens and that pressureized air flows through the check valve to the atmosphere.

When he's cruising/idle, there's enough vacuum to open the bypass valve. But air can't be sucked in by the motor because the check valve prevents it.

He's still blowing a whole lot of air, that his turbo spent alot of energy getting into the UICP right out in the air, AFTER it has already been metered. I'd rather direct that air into the compressor helix to give the energy back to the compressor at least helping to stay spinning faster for longer. Rotational inertia is a b!tch

hrm..

 

[dsm-onster]

This still doesn't change the flow of the system between shifts. My car still dies between shifts with my BOV vented. Some don't some do. So, since the check valve makes the BOV still vent between shifts just like an atmophere vented system with out a check valve, this case of not stalling isn't because of installing the check valve . . .

Lifting the foot completely off the throttle pedal activates the idle switch. and fuel is cut completely until idle rpm. This could negate metered air issues between shifts. But I'm not into lifting completely off the throttle between shifts in a spirited run . . . And I think this function might be affected by speed input.

 

[spyderturbo007]

Fixed

Uh, no. I was right the first time. Burning fuel inside the manifold leads to increased EGT's, not decreased.

 

[clockworktoy]

Although I don't agree with The op I do give him props for getting proof that his car won't blow up this way. I have logs of my current setup vta and recirculated and I have logs of both I can post up when I get home. A 2 point difference in afr between shifts will definately have an effect on spoolup (with bigger turbos) as I have noticed and that does have an effect on performance. People need to realize that the op realizes that what he's doing isn't the right way, but instead something that won't kill his motor (at least from washing oil from the cylinder walls) and he can live with the "negligible" side effects.

 

[snakeyes711]

And if you'd just read before opening your mouth I've already explained why you need a check valve too. If you really wanted to know an answer you'd read the thread from the start. But you just want to feel good about yourself by calling others stupid. So feel free to stay out of my thread.

You got it bro,I'm unsubscribing right now. AND, I did want to know an answer, and I did read this thread from the start. BUT, I never called anyone stupid, I didn't see a need, or gain for doing this. Plus, you avoided my question, what are three good reasons to do it, by mouthing off with personal attacks. Way to go.

 

[tkelly27]

I don't have a log and at one point I definitely meant to make one but I haven't gotten around to it and I'm putting the car away for the winter tomorrow so it isn't going to happen at the very least until spring.

Try recirculating again, did you switch to venting right when you switched to SD? If so I can definitely tell you that you wouldn't notice a difference with all the other things going on while you try and get the car tuned. I started by tuning my car for SD with the MAF still on then started venting with that same setup just to see if I liked the sound and because I could. This gave me a fair amount of insight to the differences in performance with changing ONLY whether or not some air got shot back at the turbo inlet. Later I switched my intake tube and had to re-tune a little bit.

No, I ran around with the same setup as mass air when I switched to SD. The only difference was a cheap filter on the end of the pipe vs. the mass air sensor and a paper filter.

I'm unsure how or why it would cause an effect. I've not seen any dedicated race cars that recirculate, actually most use the 50mm tial. Perhaps in auto-x or rally this isn't the case? Even if you recirculate, you are dumping the intake pressure back into something that's at atmospheric pressure. You're not feeding the turbo compressed air. Even if it is, it will want to expand and displace the incoming air anyway.

I think it was in maximum boost that I had read that the bov's spool recovery attribute comes from removing the work that the compressor has to do.

 

[Sam@RRE]

To the OP:
That's cute I guess. Im running SD in my DD so I do vent for fun, but going to be building a recirc tube to recir. I feel boost response between shifts are better.

 

[forcefed86]

The fastest DSM don't have a stock ecu or alter their perfect system to whoosh noises ... hell some of them don't even lift off of the throttle the entire run.

And that is my point. If recirculating the BOV really helps spool the turbo between shifts enough to cause a major difference the pros would all do it.

I've already proven the mixture doesn't go overly rich or lean during the "blow-off". Also proven that idle and cruise conditions are not effected.

Your talking about MPG loss? When? At WOT while boosting? Personally I'm not to concerned about my MPG loss for a 10th of a second while shifting.


This is all stated in the first post. But I'll repeat it for the stubborn.

With the factory ECU/chip AFR's are in the low 10's to mid 9's at upper rpm and boost levels. While recirculating during a shift AFR's leaned out to 12.5 or so for a tenth of a second. Then richened back up to 9.5:1.

While venting the BOV AFR's leaned out to low to mid 10 AFR's during a shift. So they were slightly richer than recirc. But still leaner than the factory maps. Hardly enough to cause a noticeable difference, or major "side-effects".

This thread makes me want to cry.

I applaud the time you took to obtain these results, but all it's done is reaffirm what we have been saying since day one. The DSM ECU expects certain conditions, such as a recirculated BOV. It assumes that previously metered air will be recirculated back into the intake post MAS and uses this assumption in its fuel delivery calculation.

By removing this metered air, you are altering the AFR. This has repercussions, such as fouled plugs, increased EGT's, unnecessary unburnt fuel entering the cat, etc. It's your car and you are more than welcome to do with it as you please, but it was designed that way for a reason. If you really want a louder BOV, why not just switch to DSMLink and run a SD setup?

And while I appreciate you not being rude. I disagree with you and have already proven you incorrect. And if you'd read the first post it would explain this.

No fouled plugs, excessive fuel, washer cyl walls, or any other nonsense. You can tell me I'm wrong til your blue in the face. Go do it as I have. And you'll see that what is commonly accepted as truth is in fact myth.

People keep saying give 3 good reasons to vent. I say give me 3 good reasons not to. With real world tests and proof. Because I've proved all of them wrong 100% except possibly a tiny increase in spool speed. Which with my specific setup was also negligible.

He's still blowing a whole lot of air, that his turbo spent alot of energy getting into the UICP right out in the air, AFTER it has already been metered. I'd rather direct that air into the compressor helix to give the energy back to the compressor at least helping to stay spinning faster for longer. Rotational inertia is a b!tch

This is true, but you also have to take in to account that the air is already been heated by compression of the turbo. So I'd be blowing less dense hot air back into the turbo instead of fresh cool air.

Also you have to take the setup being tested into account. I've tested my setup both ways and shown little to no difference in 1/4 mile times. Gtech graphs the entire RPM band. They are almost identical. Thats good enough proof for me.

You got it bro,I'm unsubscribing right now. AND, I did want to know an answer, and I did read this thread from the start. BUT, I never called anyone stupid, I didn't see a need, or gain for doing this. Plus, you avoided my question, what are three good reasons to do it, by mouthing off with personal attacks. Way to go.

Your first sentence was.

It doesn't take a genius to figure this out, when you think about it...Right?

IMO thats the same thing as calling someone an un-genious....I.E. Stupid. And your wrong I've already answered your questions many times in fact.

To the OP:
That's cute I guess. Im running SD in my DD so I do vent for fun, but going to be building a recirc tube to recir. I feel boost response between shifts are better.

Well as long as you think It's cute, I'm happy! It may help you... I look forward to some AFR logging and gtech passes after you do so. Personally my little turbo spools so fast it doesn't make a piss of difference.

 

[#40Fan]

ForceFed, you're beating your head against a wall trying to explain this. You know it works.

 

[dsm-onster]

It works for him. It didn't work for me. My car stalled. It didn't work for Jusmx141. It probably does work for some other guys. And on the other hand, the same amount it doesn't work for. He just proved that his car doesn't stall.

Did you let completely off the gas activating the idle switch causing basic fuel cut? Or did you roll out of the throttle like I do when I'm shifting?

I don't know why you're so adament. It's not a big deal. Some have felt a loss in performance from doing this other's havn't. It's proven that it's possible that you will or won't from setup to setup. In the sense of practicality, this is still a waste. You invested in adding a part that ads complecity and could fail. And if your car were one that stalls, then it would be one that does run super rich between shifts with a vented bypass valve, check valve install or not. For mine, going to below 9:1 A/F ratio which I saw was not an option for me. I had just rebuilt the motor and put alot into it. Under 9:1 is where you CAN have cylinder wash.

FYI un-genious is anyone under 140IQ . . . Gifted is anyone over 120 IQ

 

[the_mork]

For being a troll you're fairly sensitive about being called un-genius. I think if someone called me that in real life I would be far from offended (I might ask what they were smoking) but on the interblagosphere how can you get upset about something like that?

Also why didn't you just go to a bov setup that isn't open at idle? An SSQV, Synchronic, Tial, or even a TurboXS bov all do what your check valve does without the ugly check valve.

 

[Fabian]

honestly, I've ALWAYS gotten shit from other dsm owners on here and other forums for running VTA on my bov. But I've never once had a problem with my cars stalling or bucking? Dont ask me why, I'm definitely no master mechanic. But I've never had a problem with doing so. Of course, I'm not looking to create a shitload of power out of my cars either. They've always been daily drivers. Even now when I have an awd and fwd talons I only reach for 300-350hp out of either one.

But I'd like to atleast THANK forcefed86 for showing his logs and sharing his info with us. I've had the type-s, ssqv, and RFL on my cars and really never had a problem except with the type-s not opening enough when letting off the throttle and creating compressor surge. But I even did the single spring mod on that and it took care of that problem.

 

[dsm-onster]

So now we're at 50/50 on this thread with guys who have been ok with venting and those that have had problems. . .

. . . For everyone else, it's your call. Will it work? You can go find out. If you stall, then you know what your problem is. . .

 

[TRBOBLU]

Im really not sure what the OP thinks he is trying to prove. Apparently he thinks he has come up with some new controversial mod. Listen it is 2009. A simple search on ANY dsm forum would have showed people have been doing this since before 2003 and it works great for some and others not so great. What are you trying to prove? Ive been venting since I bought my car in 2001 and just got a GM MAF a little over a year ago(2g maf before). My car ran pretty good(richer in between shifts) and did not have a large amount of noticeable side effects. And to a reply you made on the first page about 2 points a/f not being very big. Are you kidding? 2 points on WOT is the difference between a car running like crap from being pig rich to a car that pulls like a raped ape. 2 points in between shifts usually results in a stumble if you let off the gas. Anyway, Im glad venting works for you, just like it worked for me. I don't think anyone is going to give you a cookie for proving something DSMer's have been doing for the better part of a decade and beyond.

EDIT: Guess I should add that for over 5 years of my venting I was running a 1g BOV not my current TIAL.

 

[spyderturbo007]

And while I appreciate you not being rude. I disagree with you and have already proven you incorrect. And if you'd read the first post it would explain this.

Just because no repercussions have manifested themselves yet according to what you are posting, doesn't mean it won't cause problems down the road.

No fouled plugs, excessive fuel, washer cyl walls, or any other nonsense. You can tell me I'm wrong til your blue in the face. Go do it as I have. And you'll see that what is commonly accepted as truth is in fact myth.

Of course there is excessive fuel. How can you possibly dispute that fact? Even your own "findings" show a richer AFR, which can only be caused by excessive fueling.

Yes, I have tried removing the BOV recirculation hose, right after I got the car. I thought I would look "cool" with a loud BOV.

Then, once I found out the car fell on it's faces and carried on like a cranky old man, I put the hose back on.

Other than your WBO2, do you have any other data? Perhaps a ECMLink log, FT's, O2 voltages, etc?

 

[forcefed86]

It works for him. It didn't work for me. My car stalled. It didn't work for Jusmx141. It probably does work for some other guys. And on the other hand, the same amount it doesn't work for. He just proved that his car doesn't stall.

Did you let completely off the gas activating the idle switch causing basic fuel cut? Or did you roll out of the throttle like I do when I'm shifting?

I don't know why you're so adament. It's not a big deal. Some have felt a loss in performance from doing this other's havn't. It's proven that it's possible that you will or won't from setup to setup. In the sense of practicality, this is still a waste. You invested in adding a part that ads complecity and could fail. And if your car were one that stalls, then it would be one that does run super rich between shifts with a vented bypass valve, check valve install or not. For mine, going to below 9:1 A/F ratio which I saw was not an option for me. I had just rebuilt the motor and put alot into it. Under 9:1 is where you CAN have cylinder wash.

FYI un-genious is anyone under 140IQ . . . Gifted is anyone over 120 IQ

I'm adamant because I'm tired of people telling me what won't work and what I can't do. U say this has been done before and works for some and not others. IMO it will work for everyone. Show me another documented thread or instance where someone has installed a check valve and is venting as I have. Did you have the check valve installed when your AFR's dipped down to 9:1 when shifting? Did you modify the BOV for high boost so it won't leak? If you own a factory original car with no other issues I believe this will work for everyone.

For being a troll you're fairly sensitive about being called un-genius. I think if someone called me that in real life I would be far from offended (I might ask what they were smoking) but on the interblagosphere how can you get upset about something like that?

Also why didn't you just go to a bov setup that isn't open at idle? An SSQV, Synchronic, Tial, or even a TurboXS bov all do what your check valve does without the ugly check valve.

Ooo now I get to be a troll too, sweet! Who said anything about being
upset? I could care less, but I'm not going to be civil to close-minded D-bags.

And contrary to what u may believe I don't care what others think about my car or engine bay. I build my cars for me. Personally I think it's pointless to waste money on aftermarket products when I can make the factory product perform just as well for an additional 9 dollars. U can't even see the check valve the way I have it setup now.

Im really not sure what the OP thinks he is trying to prove. Apparently he thinks he has come up with some new controversial mod. Listen it is 2009. A simple search on ANY dsm forum would have showed people have been doing this since before 2003 and it works great for some and others not so great. What are you trying to prove? Ive been venting since I bought my car in 2001 and just got a GM MAF a little over a year ago(2g maf before). My car ran pretty good(richer in between shifts) and did not have a large amount of noticeable side effects. And to a reply you made on the first page about 2 points a/f not being very big. Are you kidding? 2 points on WOT is the difference between a car running like crap from being pig rich to a car that pulls like a raped ape. 2 points in between shifts usually results in a stumble if you let off the gas. Anyway, Im glad venting works for you, just like it worked for me. I don't think anyone is going to give you a cookie for proving something DSMer's have been doing for the better part of a decade and beyond.

EDIT: Guess I should add that for over 5 years of my venting I was running a 1g BOV not my current TIAL.

Because instead of just saying "some work and some don't" I chose to find out why. I believe this will work on all (1g's at least) with OEM original or mildly modded setups.

U say this is nothing new, yet I've never seen or heard of anyone doing this with the check valve installed as I have.

As far as 2 points being a big deal, the factory recirculating method leans out the mixture 4 points. I don't know about you, but I don't want my fuel ratios jumping up into the 14's between shifts. IMO it's to lean. More importantly, if it was enough of a difference to make the car run like "raped ape" then it would have shown up on the quarter mile passes I logged. Yet it didn't make a difference, as I said it wouldn't.

Just because no repercussions have manifested themselves yet according to what you are posting, doesn't mean it won't cause problems down the road.



Of course there is excessive fuel. How can you possibly dispute that fact? Even your own "findings" show a richer AFR, which can only be caused by excessive fueling.

Yes, I have tried removing the BOV recirculation hose, right after I got the car. I thought I would look "cool" with a loud BOV.

Then, once I found out the car fell on it's faces and carried on like a cranky old man, I put the hose back on.

Other than your WBO2, do you have any other data? Perhaps a ECMLink log, FT's, O2 voltages, etc?

Like I said I ran my old car this way for years with no issues. With the information I've collected, common sense tells me it won't harm anything.

Correct I did find it is a tad richer for a 1/10th of a second or so. So what? Did this effect performance? NO. Will this cause any damage to an engine? NO.

You say you tried venting before and the car ran poorly. Did you have the check valve installed as I said? I doubt it. Without it you won't be able to vent properly.

I did just buy an old m100 palm pilot. I've got MMCD 1.8 at the moment. Although 02 voltages are pretty useless unless your at idle or cruise. I could log any other parameters though.... I'll play with it some this weekend. I've never used one before.

 

[EclipticalGS]

Just for peace of mind, the "Pros" which you are reffering Usually....
A. Dont even use a air filter or intake tube....

B. Even if they had an intake tube, the BOV could be 2-feet away from the tube, according to the pro's set-ups.

C. I cant really see too much performance loss VTA on a "pro's" car that has a monster turbo pushing 35+ lbs of boost anyway, The BOV pressure recirc'd wouldn't really even help spin the turbo.

D. Points B and C, make reason for Point A.....Which resolves the reason why pro's don't Recirc.

As stated before, most "pro's" no-lift shift, have a dogbox, or have auto's.

Your with this post.
that it worked for you supposedly, but Count how many people told you it messed up their cars...Personally, metal recirc. with Type-S bov = lovely