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Reply With Quotei'm PRETTY sure (feel free to correct me if i'm wrong) that a BOV releases pressure quicly to let the turbo spool up again, thus decreasing and sometimes removing turbo lag, and a DV just recyles the pressure.
can anybody explain the difference between a blow off valve and a diverter valve to me? ive always wanted to know.. thanks in advance
i'm PRETTY sure (feel free to correct me if i'm wrong) that a BOV releases pressure quicly to let the turbo spool up again, thus decreasing and sometimes removing turbo lag, and a DV just recyles the pressure.
well mechanically i understand that difference, i guess what i realy want to know is why is it better for certain applications to have their unused pressure vented to atmosphere (BOV), rather than recycled like you said (DV)?
a bov is to stop compressor surge. when the turbo is spooling, and pumping air, and the throttle body closes, all this air has no place to go. plus, it sends a reverse wave back to the turbo, and the reverse pressure/wave can actually make the compressor turn backwards. this is not only bad for the turbo, but when the throttle opens again, there is no boost. a diverter valve is more of a crude wastegate, where when a set boost is reached, the valve opens, and dumps excess boost back into the inlet tract, or wherever, and the turbo keeps spinning. in the early days, before the wastegate, the diverter valve was used a lot to control boost. on a karmann mas car, like the mitsubishis, if the bov is vented to atmosphere, so it makes the real cool rice sound, if no fuel control is used, this will make the car stall. what happens is the air that goes thru the mas is counted, and fuel is adjusted by the ecu for this air. when the air is expelled thru the bov to the atmosphere, now the fuel is too rich, and the car will stall between shifts.
Originally Posted by ken inn
You are inaccurately generalizing about "rice" sounding BOV's. NO not all DSM's will stall if you vent it. PERIOD. Go read dsmtalk if you dont' believe me. All the guys say it's a freak occurance and it is not predictable. The definition of "rice" as being applied to someone who has a BOV is really getting on my nerves. If i just spent 3000 or more dollars to strap on a turbo, you god damn better know that I have one, and you better hear it blowing off. If it is the guy's choice to do it, let them do it and quit tryign to tell people that it is "rice". Besides your claim of "no fuel control" isn't even warrented. If you run a turbo on a 4g64, you will need some form of fuel management unless you really are retarded. An AFC auto-compensates for the "rice" BOV's....thus I am further baffled with your claim.
I also disagree with the "rice" term being thrown around here. Turbo's can be very clean applications. Perhaps that "rice" label should be left for electronic bov type noises that are triggered for N/A cars.
As for the DSM's that dump internally. I have never heard of someone being able to dump into the atmosphere without the use of a VPC. I've even heard it still happening with the VPC (probably untuned I imagine). With a VPC a AFC is not NEEDED persay, but probably advised.
you wont find a better explanation then that in any dictionary
:: applause! ::
yah, well, if you go back and read, what i said was a KARMANN MAS type of car will run rich and stall(dunno about the latest galants, but my car and most of the other mitsus still use the karmann mas). because the air that is expelled to atmosphere has already been counted, and the fuel has been adjusted for it. if the air is not there, then there is too much fuel. and afc will NOT compensate for this. go back to dsm talk and ask. if you're REALLY brave, go to team nabr, and post that. if you want to vent your bov, have at it, it's your car. i prefer NOT to advertise what i got, and most of the other vr4 owners feel the same way. or, since everyone is so picky, most of the 1991-1992 usa galant vr4 E39a owners feel the same way.
yeah, about the rice comments: turbo = more power. so if its rice in your opinion, it'll probably kick your ass now. especially on those "rice" low end hondas, light as fuck, little power goes a long way. the new GReddy Turbo kit for the 03 civics will make you get on ur knees and beg not to get your ass kicked........but i still hate civics.
You would have to be brave to go to team nabr :shock:
My response was based on my knowledge of 1st gen DSM's... more specifically my 91 Talon that I had and from what I've learned, a VPC is needed to dump into the atmosphere. My bad if its different and/or i'm wrong.
Wait a minute, are you talking to me or the other guy? b/c you're reply was talking about just the AFC and I was including the VPC which sends that needed signal.
i was referring to the post about the afc. you are correct about the vpc. and, to answer the post about a turbo kicking my ass, bring it on. you can see from my sig that i also have a factory turbo car, also, fmic, pipes, hks cams, water injection, 2.5 o2 eliminator downpipe, random technologies cat, certified catback, evo 6 560's, TRE ported big 16g(and going to an fp sleeper) at 18 lbs boost, yada, yada. bring on your honda. you may win, but i guarantee you will WORK for it. and, back to dsmtalk, one of the latest post deals with this topic:
http://www.dsmtalk.com/forums/showthread.p...p?postid=955426
and the loud bov is also referred to as rice. also, check out the posts about running rich with the karmann mas. to each his own, i prefer not to vent, you wanna vent your bov, have at it. my post about the car running rich is correct.
Yea, you're right. I mis-read your original post and I thought your second post was about my comments. Two thumbs up, I agree with you... except for the "rice" label. I have a TurboXS bov on my avenger and enjoy the sound. That doesn't make my car any bit of rice. Of course I have no option... otherwise my turbo woulda been torn to pieces as stated in your first post with the boost coming back when the TB closes. To each is own fo' sho'. I see rice as unclean modifications. A noise, esp if its functional doesn't really hold any rice value.
All DSMs/galants work with a Karman MAS, read any installation manual for an AFC, you have to plug that data in when you set it up. Besides, there is no reason to be a douche bag and argue about "you are rice for having a BOV that is loud"...give me a fucking break. Find something better to argue about and be on with it.
All DSMs/galants work with a Karman MAS, read any installation manual for an AFC, you have to plug that data in when you set it up. Besides, there is no reason to be a douche bag and argue about "you are rice for having a BOV that is loud"...give me a fucking break. Find something better to argue about and be on with it.[/quote]
did i miss something here? have you ever USED an afc? i've had one on my car for at least 3 years. and it wont compensate for venting a bov to atmosphere. you want to vent your bov, which i bet you dont even HAVE, go for it.
did i miss something here? have you ever USED an afc? i've had one on my car for at least 3 years. and it wont compensate for venting a bov to atmosphere. you want to vent your bov, which i bet you dont even HAVE, go for it.[/quote]
Yes, you are a mother fucking tard. RTFM. page 6 from APEXI directly
http://www.apexi-usa.com/productdocumentat...S-AFC2Final.pdf NOW pull down your pants, and get anally molested. For those who don't have adobe...
"In a turbo equipped vehicle with a hot-wire type airflow meter, this type of controller provides a preventative funciton for engine stall due to blow back during throttle return."
Once again, quit being a douche. It can work as that with the right type of MAS. Ass.
hey butt fuck, you know the difference between a karmann and a hot wire? if you HAD and afc, you would know. if YOU check the instructions, you will see there are DIFFERENT SETTINGS for hot wire or karmann, BECAUSE THEY AINT THE SAME.
It can work as that with the right type of MAS. Ass.
agian...like i said..i never said it was going to work on a galant Karman mas,a friend of mine just finished a QR sentra and it defiitly sprays out no problems.
Also, why am I even defending myself...DJ galant on here has a big ass Apexi BOV if memory serves me right. He doens't have any problems...
Again, like I said in the beginning, the dsmltalk guys generally say that the BOV problem on 2g cars is isolated and is not something that will always happen.
Since you guys are fiending for rice so much:
http://cgi.ebay.com/ebaymotors/ws/eBayISAP...item=2439630195
diverter and blow off valves Are the same
just different terminology
BOV = dsm-world
Diverter Valve - WV world
Volvo guys call them bypass valves I think
if you look up the BOV in CAPS
it's actually called A compressor bypass Valve or something like that.
their purpose:
preventing excessive post-turbo pressure when the butterfly valve in the throttle-body is Shut, and the impellar is spinning from High RPM.
also, This prevents the impellar from coming to a SLAMMING Stop
imagine going From 150k Rpm to ~5k Rpm in a split second....
NOT a good thing for Turbos.
they are more a Tool for longevity of turbos..
all turbo cars will run fine W/out One.
however; shytting the throttle-body And Stopping the turbo's momentum between Shift means you have to Re-spool the turbo EVERY time you let off the accel.
This looks like that thing that the drunk black guy installed on his car and then ran a stop sign while he was demonstrating it. There was a video on here about it a long time ago. It's a classic.... :laughing:
Chip
2000 Basalt Black Metallic GTZ
(Paint Code: Porsche LC9Z)
Genuine experience carries a lot more credibility than the ability to answer a question.
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