blow-off valve?
- Thread starter 87MNGN
- Start date
equalizer442
Active Member
- Joined
- Oct 23, 2002
people use them, some people swear to them, but there not needed so as far as they go in my book there rice.
V6UnderPressure
The Artist FKA Scott4DMny
- Joined
- May 27, 2001
I did, I had mine welded to the side of the up pipe although most say to put it on the intercooler neck just before the up pipe but I figure its close enough. Its recommended for those high boost bigger turbos!
Scott
Scott
Vendor Defendor
Out the window
- Joined
- Nov 25, 2002
its possible, most people here would say its a waste of money, check out this old thread..
http://www.turbobuick.com/forums/showthread.php?s=&threadid=56999
http://www.turbobuick.com/forums/showthread.php?s=&threadid=71270
the second one has a really good summary by turbodave about half way down...
-Neil
http://www.turbobuick.com/forums/showthread.php?s=&threadid=56999
http://www.turbobuick.com/forums/showthread.php?s=&threadid=71270
the second one has a really good summary by turbodave about half way down...
-Neil
Turbosix6
PORSCHE KILLER
- Joined
- May 31, 2001
I run one with my TE-60 and I feel that it helps alot when backing off at higher speeds and then getting back on the throttle.
Also, if you go to the track alot it will help you even more (your turbo that is)when you are doing your burnout and release the gas pedal - effectivly trying to spin your turbo in reverse from 25,000++ rpm.
Bottom line is, It doesnt allow the turbo to stall completely with the blow-off valve - also I enjoy the warning it gives to Vettes, vipers, Z's etc... when you come up next to them and release the throttle- chiiissshhh
Also, if you go to the track alot it will help you even more (your turbo that is)when you are doing your burnout and release the gas pedal - effectivly trying to spin your turbo in reverse from 25,000++ rpm.
Bottom line is, It doesnt allow the turbo to stall completely with the blow-off valve - also I enjoy the warning it gives to Vettes, vipers, Z's etc... when you come up next to them and release the throttle- chiiissshhh
equalizer442
Active Member
- Joined
- Oct 23, 2002
thats why i roll out of the bleach box and release the throttle slowley
EFFNQWKWE4
New Member
- Joined
- Nov 6, 2002
I have one on my car, helps with spool up if you have to let off the gas, then back on quickly. Some consider them a waste of money, but they're designed to save your turbo's bearings. They can't be bad for your car, but most likely not necessary.....just a matter of personal opinion and taste. If I wasn't so computer illiterate, I'd post a pic of mine. It's mounted on the up-pipe, just above the intercooler.
My thoughts on BOV's from a previous thread:
"Yes, you will get many differing opinions on the subject. It pretty much boils down to the following observations.
1. There are a LOT of new and younger guys getting involved in the Turbo Buick craze. They bring a lot of ideas and generallities that they've picked up from the import community. (rule of thumb there is not turbo car should be without one).
2. Those of us that have been involved in the Turbo Buicks now for the last 16+ years are generally of a different generation, and learned how these cars work and perform based on experience and a "different set of rules".
3. For the most part these cars absolutely DO NOT need BOV's, for any reason other than to make that obnoxious noise that so many of the "importers" love to hear.
These cars are automatic tranny'd, so that alone negates the need for the BOV.
They also suffer very very few failures as a result of compressor slam or surge (more annoying than fatal).
I've owned a "few" Turbo Buicks over the past 16 years, and can honestly say I've never suffered a single turbo failure of any kind as a result of not running a BOV. The one failure I did have was a result of FOD (foriegn object damage), pieces of a Champion spark plug ate the turbine wheel (the one and only time I've ever run those things)
And trust me, anyone that knows me can tell you, I'm extremely hard on my cars
Oh, and BTW, no, you also don't need one just because you're running a front mount.
If you think you must have one, fine. Spend (waste) your money, but you won't see a single advantage, other than the afformentioned obnoxious noises. Oh and you'll have fun trying to get it setup right
I'm down off my soap box now. This is one of those subjects that just seems to strike the wrong nerve
For those of you that are die hard believers in the BOV's on Turbo Buicks, and hope to get an arguement from me, and run this thread out adnausium, forget it.
I am of the opinion that they are a pitiful waste of good money (on our cars). This is based not only on my experience, but the experience of the entire Turbo Buick community that have been involved with these cars for a suitable amount of time to actually gain insight.
So, as I said, IMHO. So I will argue the point, NOT."
"Yes, you will get many differing opinions on the subject. It pretty much boils down to the following observations.
1. There are a LOT of new and younger guys getting involved in the Turbo Buick craze. They bring a lot of ideas and generallities that they've picked up from the import community. (rule of thumb there is not turbo car should be without one).
2. Those of us that have been involved in the Turbo Buicks now for the last 16+ years are generally of a different generation, and learned how these cars work and perform based on experience and a "different set of rules".
3. For the most part these cars absolutely DO NOT need BOV's, for any reason other than to make that obnoxious noise that so many of the "importers" love to hear.
These cars are automatic tranny'd, so that alone negates the need for the BOV.
They also suffer very very few failures as a result of compressor slam or surge (more annoying than fatal).
I've owned a "few" Turbo Buicks over the past 16 years, and can honestly say I've never suffered a single turbo failure of any kind as a result of not running a BOV. The one failure I did have was a result of FOD (foriegn object damage), pieces of a Champion spark plug ate the turbine wheel (the one and only time I've ever run those things)
And trust me, anyone that knows me can tell you, I'm extremely hard on my cars
Oh, and BTW, no, you also don't need one just because you're running a front mount.
If you think you must have one, fine. Spend (waste) your money, but you won't see a single advantage, other than the afformentioned obnoxious noises. Oh and you'll have fun trying to get it setup right
I'm down off my soap box now. This is one of those subjects that just seems to strike the wrong nerve
For those of you that are die hard believers in the BOV's on Turbo Buicks, and hope to get an arguement from me, and run this thread out adnausium, forget it.
I am of the opinion that they are a pitiful waste of good money (on our cars). This is based not only on my experience, but the experience of the entire Turbo Buick community that have been involved with these cars for a suitable amount of time to actually gain insight.
So, as I said, IMHO. So I will argue the point, NOT."
hey turbodave, i'm 21 and one of the younger guys in the world of tr's and i have never had anything to do with the import community nor do any of their ideas. I have a bov and its not because a turbo car must have one it was a suggestion that i took from a qualified source and said it might help with turbo life or it might not but i put one on. Just want to let you know that I am not influenced by imports in anyway.
I'm 18 years old and have never been involved with the import stuff. BUT there are A LOT of people my age that are around my age group that try to bring stuff from the import community to the TR stuff.
SOOO... with that said.. here is my opinion on BOV. I'm not saying that they don't help save the turbo but i put 163,000 miles and counting on a turbo and i have no BOV. I think most people buy it for the sound it makes and try to justify it with other reasons. I agree that they are not needed on these cars. Once you have an 8 second car, it is probably a different story. I am no expert here, but i feel that they aren't needed and the money could be better spent elsewhere.
Scott
SOOO... with that said.. here is my opinion on BOV. I'm not saying that they don't help save the turbo but i put 163,000 miles and counting on a turbo and i have no BOV. I think most people buy it for the sound it makes and try to justify it with other reasons. I agree that they are not needed on these cars. Once you have an 8 second car, it is probably a different story. I am no expert here, but i feel that they aren't needed and the money could be better spent elsewhere.
Scott
Much much more money has been "un-necessarily" spent on FMs (900-1100 + cooling system upgrades) on cars that do not "need " them than for any other single item.
That's probably the biggest example of "style-over-substance" in the Buick kingdom, and some might say the purest manifestation of TR "rice" yet.
"Wow, that car must be FAAAAAAASSSSSSSSSTTTTT, it's got a FM!!"
HTH
That's probably the biggest example of "style-over-substance" in the Buick kingdom, and some might say the purest manifestation of TR "rice" yet.
"Wow, that car must be FAAAAAAASSSSSSSSSTTTTT, it's got a FM!!"
HTH
Steve Wood
Active Member
- Joined
- Jul 18, 2001
Being in agreement with Dave and having a similar amount of experience, I always wonder who these qualified sources are.
John Craig and Harry H. both come from Garrett and neither have ever tried to sell me a blow off valve. At various times in the past, I believe both have stated they are not needed. I consider them to be qualified sources.
Yes, sometimes us old guys don't like to learn new things-particularly when there is no evidence that they deliver a benefit equal to their cost. On the other hand, we usually have money to spend for those items that do.
Buy one of those bov sound generators...it will make a lot of noise and will not screw up the performance of the car if it goes off at the wrong time.
John Craig and Harry H. both come from Garrett and neither have ever tried to sell me a blow off valve. At various times in the past, I believe both have stated they are not needed. I consider them to be qualified sources.
Yes, sometimes us old guys don't like to learn new things-particularly when there is no evidence that they deliver a benefit equal to their cost. On the other hand, we usually have money to spend for those items that do.
Buy one of those bov sound generators...it will make a lot of noise and will not screw up the performance of the car if it goes off at the wrong time.
Steve Wood
Active Member
- Joined
- Jul 18, 2001
Sure...everyone has opinions
I tried one for awhile so I do have some experience to back up my opinon-at least in this case....
Of course Garret has them..they are a benefit on manual transmissioned cars when plumbed back into the intake to the turbo.
I guess one could make an argument that looping the outlet back thru the maf might improve air metering but I think that is more a theoretical argument than a practical one.
I have put a lot of miles on my 45 and it is still very tight-no sign that the lack of a bov has done any damage. Between my own experience and that of those who do it for a living, I believe they are a waste of money. If someone proves differently, I shall be happy to change my mind. AT my age, however, I ain't gonna hold my breath just in case it takes awhile.
I tried one for awhile so I do have some experience to back up my opinon-at least in this case....
Of course Garret has them..they are a benefit on manual transmissioned cars when plumbed back into the intake to the turbo.
I guess one could make an argument that looping the outlet back thru the maf might improve air metering but I think that is more a theoretical argument than a practical one.
I have put a lot of miles on my 45 and it is still very tight-no sign that the lack of a bov has done any damage. Between my own experience and that of those who do it for a living, I believe they are a waste of money. If someone proves differently, I shall be happy to change my mind.
AT my age, however, I ain't gonna hold my breath just in case it takes awhile. Quicker spool up??
I agree with Dave.. and Steve. A blow off valve is just a relief valve. It will open when the pressure in the intake exceeds a set point, which should be higher than the MAX desired boost by a pound or two. If you want more boost in first/second gear than in third/fourth, the blow off valve will have to be set so high that it doesn't work for third gear. Also, when the pressure in the system drops below the set-point, the valve will close, so the turbo will see at least that back pressure, and will slow down.. so why is there a "quicker spool"?? Also, if it is vented BACK INTO THE ENGINE, how will it relieve the pressure? I guess you could run the discharge back to the turbo inlet, and kill the sound, is that waht you mean? There are supercharger bypass valves that allow intake air to bypass the supercharger, while the supercharger maintains a pressure upstream of the bypass valve, but those valves are different from what we're talking about, and they DO provide quick throttle response. If the car in question has a very small intake volume, between the turbo and the throttle body, THEN compressor slam may be significant, and cause bearing problems. But, especially on an intercooled car, there is such a large volume to "cushion" the shock, I don't think slam will cause problems. The momentum of the spinning compressor will be used up compressing the air in the system, and after that, the air will try to go backwards, out through the turbo. BUt all that will take a second or so. Maybe somebody should design/build a check valve, to keep the air from going backwards...
I agree with Dave.. and Steve. A blow off valve is just a relief valve. It will open when the pressure in the intake exceeds a set point, which should be higher than the MAX desired boost by a pound or two. If you want more boost in first/second gear than in third/fourth, the blow off valve will have to be set so high that it doesn't work for third gear. Also, when the pressure in the system drops below the set-point, the valve will close, so the turbo will see at least that back pressure, and will slow down.. so why is there a "quicker spool"?? Also, if it is vented BACK INTO THE ENGINE, how will it relieve the pressure? I guess you could run the discharge back to the turbo inlet, and kill the sound, is that waht you mean? There are supercharger bypass valves that allow intake air to bypass the supercharger, while the supercharger maintains a pressure upstream of the bypass valve, but those valves are different from what we're talking about, and they DO provide quick throttle response. If the car in question has a very small intake volume, between the turbo and the throttle body, THEN compressor slam may be significant, and cause bearing problems. But, especially on an intercooled car, there is such a large volume to "cushion" the shock, I don't think slam will cause problems. The momentum of the spinning compressor will be used up compressing the air in the system, and after that, the air will try to go backwards, out through the turbo. BUt all that will take a second or so. Maybe somebody should design/build a check valve, to keep the air from going backwards...
V6UnderPressure
The Artist FKA Scott4DMny
- Joined
- May 27, 2001
Makes you wonder why ATR sells one then. Dave, that was good information. However, your addressing it with the import community was a little "idiotic". I too was recommended to get one by some experienced technicians. This is an opinion just as everyone elses. Many can argue about the Volt Booster (a gimmick in my opinion). When the throttle body closes, all that boost puts pressure on the turbo bearing. Its a true statement. Automatic Trans or not, its there. I don't believe for a second that it does absolutely no good. But, I guarantee you we dont follow the imports. Not sure why you pretty much got smart in your post here. But we are here to help each other, not roast each other.
Scott
At the time I made that post I had been in a long winded discussion with some ricer's about the benefits of BOV's and their subsequent waste in the T/R community.
I didn't say they didn't have a place. Of course they're sold by the big turbo manufacturers. They definately ARE required on a stick car!! And as was mentioned, even on automatic cars that have very little intake volume between the compressor and intake valves.
But in our case neither of those requirements come to bare. Compared to most turbo cars, even our stock setup has a TREMENDOUS amount of intake volume, more than enough to cusion the shock.
To say they must be needed just because ATR sells them, well.... I wont even go there (even though I have their exhaust system on my cars, and wouldn't have any other).
Anyway, there's more than ample evidence over the last 17+ years to prove they aren't a requirement on a turbo regal to justify recommending against such a purchase by any of the newer T/R folks looking for advice.
There are many things in the T/R community still being marketed today that I consider a rediculous waste of money(BOV's among them), and will continue to campaign against them, even though some of my favorite vendors still choose to sell them.
I didn't say they didn't have a place. Of course they're sold by the big turbo manufacturers. They definately ARE required on a stick car!! And as was mentioned, even on automatic cars that have very little intake volume between the compressor and intake valves.
But in our case neither of those requirements come to bare. Compared to most turbo cars, even our stock setup has a TREMENDOUS amount of intake volume, more than enough to cusion the shock.
To say they must be needed just because ATR sells them, well.... I wont even go there (even though I have their exhaust system on my cars, and wouldn't have any other).
Anyway, there's more than ample evidence over the last 17+ years to prove they aren't a requirement on a turbo regal to justify recommending against such a purchase by any of the newer T/R folks looking for advice.
There are many things in the T/R community still being marketed today that I consider a rediculous waste of money(BOV's among them), and will continue to campaign against them, even though some of my favorite vendors still choose to sell them.
Turbosix6
PORSCHE KILLER
- Joined
- May 31, 2001
Well, I'll stick with mine because it definitely helps re-spool-up if you have to release the throttle while blasting down the highway.
Regardless of whatever anyone says, blow-off valves reduce compressor stall, when you release the throttle fully or partially.
So, don't knock it till ya try it.
Regardless of whatever anyone says, blow-off valves reduce compressor stall, when you release the throttle fully or partially.
So, don't knock it till ya try it.
Rogue Leader
Eat my valvestem caps!!!!
- Joined
- May 25, 2001
If I may throw my small wrench into the arguement here... While I do dragrace my TTA I also autocross, and its noticeable the time that it takes to let the boost pressure out and the turbo to re-spool whenI let off he gas and then get back on quickly... A BOV seems like someting that could help in this situation???
