99 gst turbo BOV

:banghead:
i have a 99 gst and every thing is stock. the bypass valve/blow off valve (their the same thing right?) ide like to replace it with a ssqv BOV that releases to the atmosphere. i had heard that making the blow off not release back into the intake will make the car run shitty, and i had heard that the stock bypass valve really had two purposes a BOV and a boost regulator to keep the car from getting too much boost? is this true?

:banghead:
i have a 99 gst and every thing is stock. the bypass valve/blow off valve (their the same thing right?) ide like to replace it with a ssqv BOV that releases to the atmosphere. i had heard that making the blow off not release back into the intake will make the car run shitty, and i had heard that the stock bypass valve really had two purposes a BOV and a boost regulator to keep the car from getting too much boost? is this true?

False. The BOV does not regulate boost at all. The wastegate technically controls the boost by opening up when x-amount of boost builds up.

You are right about the car running like shit if you vent without the proper mods. The ECU is tuned from the factory to read the air coming back into the intake from the BOV being recirculated. Without the recirculation, the car will run super rich between shifts and have problems. I should know this but can't remember off the top of my head what you need. I think a GM MAF translator. Someone will correct me if I'm wrong.

Welcome to AF!

Dave is correct. Venting your bov after the maf will cause you to run rich when ever the bov vents air.

ok so what do i need to get will it be really pricey will i be able to do it my self im pretty mechanically inclined. girve me some brands so i can start looking into it.

IN order to do it you need either speed density (link v3 aem ems megasquirt etc) Or a GM MAF with translator for 95-99 ecu's. BEST BET IS LINK> I know ;)

Just buy a bov that you can recirculate and you wont have to worry about it.

but i like to sound the blow off sound. i need that! ! !

but i like to sound the blow off sound. i need that! ! !

Then go cheap, don't buy the proper mods, vent, enjoy the sound, but don't complain when the car runs like shit.

Then go cheap, don't buy the proper mods, vent, enjoy the sound, but don't complain when the car runs like shit.

+1 do whatever you want its your car we told you what you need to know the rest is up to you,.

You're in Bridgeview? I'm right by there. If I see a 99 GST with a loud BOV running like shit... well, I can't be held responsible for my actions. You should post some pics up so I know what exactly to look for.

but i like to sound the blow off sound. i need that! ! !
Grow up.

Do you want performance or a sound? Pick one until you can afford to properly upgrade your unit.

recirculated bovs are plenty loud with a metal intake pipe.

When I vented on my 2g maf and a 1g bov, it sounded decent. It really didn't run shitty, but when I was stopped at a stop light or something every now and then the car would die and Id have to restart it. It would be fine for a couple more stop lights and do the same. I think it threw a couple CEL's too. I don't remember what they were. I think every car runs differently when venting on the stock MAF.

I just did it temporarily to see how it would sound I knew I wasn't going to keep it like that. Since then, I got a GM Maf and Translator, with a HKS SSqv. I like the sound too, that's basically why I got it. I mean what is else is the point of the MAF and translator. A little extra air I think. I guess it's all what you want to do. Vent it without doing the proper mods and take your chances, or vent it with the proper mods and dont worry about it

ok look i want to vent it with the proper mods i dont want a car that runs like shit my problem is i dont know what a GM Maf and Translator is. i always planed on doing it the right way

if you get a gm maf http://www.extremepsi.com/store/customer/product.php?productid=18407&cat=773&page=1 with this
http://www.extremepsi.com/store/customer/product.php?productid=17025&cat=773&page=1

When I vented on my 2g maf and a 1g bov, it sounded decent. It really didn't run shitty, but when I was stopped at a stop light or something every now and then the car would die and Id have to restart it. It would be fine for a couple more stop lights and do the same. I think it threw a couple CEL's too. I don't remember what they were. I think every car runs differently when venting on the stock MAF.

I really dislike posts like this. They give people false hope, so to speak, that the ECU will somehow give them a break and not act like it was programmed. This is not the case. Metered air missing is metered air missing.

ok thanks a lot. with these i wont need to reprogram my computer right? its kinda like plug and play right?

:headshakeok thanks a lot. with these i wont need to reprogram my computer right? its kinda like plug and play right?

You can mimic stock settings, but "plug and play" is not generally in a tuner's vocabulary. Invest in a logger to know what your motor is doing before you tune anything.

ok thanks a lot. with these i wont need to reprogram my computer right? its kinda like plug and play right?
Negative...

You still have to "tune it" with the translator. The GM MAF pretty much goes in your UICP so you can eliminate your stock MAF and properly vent your BOV. Even so, you still need a logger to know whats going on with the motor so you can adjust the settings of the translator to "tune it" so the car still runs good. The translator converts the readings from the GM MAF so that our ECU's know how to read it properly. When you adjust the settings of the translator it really just adjusts the readings from the GM MAF before they get to the ECU. So in theory your really not changing anything on the ECU's programming. It's all in the translator... Having this will be beneficial to you with other future mods you do.

You can read up all over the internet on tuning with the translator and using a datalogger. Do some homework on it. :wink:

Brian with an educated post finally. Good job and great info.

Brian with an educated post finally. Good job and great info.

Thanks, I actually use my brain and all it's vast knowledge from time to time still. lol :licka:

I really dislike posts like this. They give people false hope, so to speak, that the ECU will somehow give them a break and not act like it was programmed. This is not the case. Metered air missing is metered air missing.

I was just sharing some of my experiences from when I vented on a 2g MAF the improper way. I did it for a whole day and it didn't run shitty at all. It just stalled out a few times and threw out some CELs. Everybody says that the car will run shitty with it vented, but mine didn't, which leads me to believe not all cars run the same with the same mods.

I was just sharing some of my experiences from when I vented on a 2g MAF the improper way. I did it for a whole day and it didn't run shitty at all. It just stalled out a few times and threw out some CELs. Everybody says that the car will run shitty with it vented, but mine didn't, which leads me to believe not all cars run the same with the same mods.
I'm not trying to sound like a dick here, but if it stalled several times and had a check engine light then that would be running shitty in my book... :2cents:

Also, when the check engine light is on then the ECU is running in open loop mode and not running completely up to par with how it should be based off readings from your o2 sensor or wideband. So just another factor in why it would be running shitty when a BOV is improperly vented atmosphere...

Again, not trying to be a dick, just trying to let all the facts be known in the discussion.

ok thanks all this is really my first turbo car and first sports car soo its like a learning experience for me and i just want to do it the right way and not mess any thing up.

ok thanks all this is really my first turbo car and first sports car soo its like a learning experience for me and i just want to do it the right way and not mess any thing up.

The best thing you can do is read. Read, read, and read some more. I remember when I started out barely knowing anything about cars. I spent many a nights just on the internet reading tech threads and guides learning as much about the car as I could. It helps in the long run.

I'm not trying to sound like a dick here, but if it stalled several times and had a check engine light then that would be running shitty in my book... :2cents:


That's why I didn't keep it that way. I don't want my car stalling out and tripping mulitiple CEL's. Some people might not care about that though and think its worth it for the sound. That's why I figured I'd list the consequences I had with venting improperly and let whoever make their own decision. I wasn't trying to start any shit by giving false hope.

That's why I didn't keep it that way. I don't want my car stalling out and tripping mulitiple CEL's. Some people might not care about that though and think its worth it for the sound. That's why I figured I'd list the consequences I had with venting improperly and let whoever make their own decision. I wasn't trying to start any shit by giving false hope.

I didn't take it as false hope. I just wanted to cover the points as to why is throws the CEL and what it's actually doing with the ECU during that time so the OP would know if for some reason he ended going that route. But I think he will actually do it the proper way with the datalogger and MAFT. :thumbsup: