MistaScott
Abnormally Aspirated
- Joined
- Oct 18, 2003
Agreed. Thread closed!
Blow off Valve, good or bad for GN?
- Thread starter Gnx6
- Start date
Well I just came from the world of DSM's, and I feel BOV's are a good investment for long term effects on a turbo'd vehicles. Sure you can run into problems with running a MAF and a BOV, the air that will vent to the atmosphere is already accounted for by the MAF and you will run pig rich when you let off the throttle for a brief second until the ECM can figure out where that air went and re adjust it self.
Now the good part is there will be less stress on your turbo when you let off the throttle, especially in high boost situations. Now you can call them ricey and all of that and thats fine, cuz you got these idiots running 4-5 pounds on there cars and feel that a BOV is a must have because they sound cool but in that low of boost really isnt needed. They are in that respect, but do you make fun of 1000hp Skylines for having them, or 800hp Supra's? If you are running anything over 20 psi then a BOV is a good investment in my book, cuz $100 rebuilds can add up pretty quick and if you look around you can find a decent BOV for under $300 and it will save you from having your car down again for yet another rebuild.
Now the good part is there will be less stress on your turbo when you let off the throttle, especially in high boost situations. Now you can call them ricey and all of that and thats fine, cuz you got these idiots running 4-5 pounds on there cars and feel that a BOV is a must have because they sound cool but in that low of boost really isnt needed. They are in that respect, but do you make fun of 1000hp Skylines for having them, or 800hp Supra's? If you are running anything over 20 psi then a BOV is a good investment in my book, cuz $100 rebuilds can add up pretty quick and if you look around you can find a decent BOV for under $300 and it will save you from having your car down again for yet another rebuild.
BlackBeauty
Member
- Joined
- Dec 15, 2001
I think a BOV would help turbo life. But there are some downsides, which makes the final choice up to each individual person.
-make sure you get a good one that can hold a lot of boost, and won't leak.
-the stumbling after letting off the gas has already been mentioned
-just another thing to mess around with
Of course it won't help performance, I don't even know how that got brought up. The only thing it will do for auto turbo cars is help out when you let off the pedal quickly after boosting. If you can't control your foot to let off slowly, then maybe a BOV is good for you. I've been pretty good at doing this.
Some people say that a BOV is good when you get a larger-than-stock turbo, since they push more air.
-make sure you get a good one that can hold a lot of boost, and won't leak.
-the stumbling after letting off the gas has already been mentioned
-just another thing to mess around with
Of course it won't help performance, I don't even know how that got brought up. The only thing it will do for auto turbo cars is help out when you let off the pedal quickly after boosting. If you can't control your foot to let off slowly, then maybe a BOV is good for you. I've been pretty good at doing this.
Some people say that a BOV is good when you get a larger-than-stock turbo, since they push more air.
salvageV6
Daily Driver
- Joined
- May 25, 2001
Why don't y'all ask your turbo BUILDER instead of internet gooroos?
I asked Innovative directly and they said no blow off valve is needed for my GT70 turbo.
They recommended Mobil one synthetic oil instead.
Even that one was tough for me to do.
Now go email or phone your turbo builder.
And yes I know the next reply will be they probably are waiting for the rebuild money.
I asked Innovative directly and they said no blow off valve is needed for my GT70 turbo.
They recommended Mobil one synthetic oil instead.
Even that one was tough for me to do.
Now go email or phone your turbo builder.
And yes I know the next reply will be they probably are waiting for the rebuild money.
I'm hoping the car won't go too goofy when I let off the throttle. A friend in T.O. has a TT Z06 and he does an external dump and has no problems. Yes I do realize there is no performance gain what so ever. I am looking at the longevity of the turbo and towards upgrades in the future that will involve more boost and a bigger intercooler. On the Turbo Z (Although it is a stick) it will smoke a turbo in a big hurry running 13 pounds of boost with the BOV set too tight.
Here is the valve I purchased.
http://www.hksusa.com/images/?id=1160
Here is info from the Manufacturer:
http://www.hksusa.com/products/more.asp?id=792
I picked one a lot of supra guys like as this is reasonably comprable to a GN, 6 cyl Turbo, 15 to 25 psi boost, etc. Overall it seems like they are a good idea. We'll see how the driveability is when the throttle is released. ie: black smoke.
Here is the valve I purchased.
http://www.hksusa.com/images/?id=1160
Here is info from the Manufacturer:
http://www.hksusa.com/products/more.asp?id=792
I picked one a lot of supra guys like as this is reasonably comprable to a GN, 6 cyl Turbo, 15 to 25 psi boost, etc. Overall it seems like they are a good idea. We'll see how the driveability is when the throttle is released. ie: black smoke.
Originally posted by azgn
I give up.......it is your money, do with it as you please
Exactly why I no longer weigh in on this particular arguement. I guess as long as those of us that have reason to believe they're not needed in the T/R setups, that's good enough for me. There are those that absolutely will not here the message, under any common sense arguement. So, I just stay out of it and let them spend their money as they see fit.
BOVs are NOT needed on our cars unless you are running HUGE turbos well into the 70's range and even then I don't think alot of guys run one...the key here is we have AUTOMATIC trannys which most of the ricers don't have on their turbo cars (if they even have a turbo! ) we don't need to bang through the gears and the boost does not drop down to 0 everytime we shift gears...on a manual turbo car yes a BOV is needed...but on our cars it's just a waste of money as mentioned before...but do as you like!
) we don't need to bang through the gears and the boost does not drop down to 0 everytime we shift gears...on a manual turbo car yes a BOV is needed...but on our cars it's just a waste of money as mentioned before...but do as you like!Mike Licht
I was here first
- Joined
- May 23, 2001
A BOV does two things. On a throttle lift gets rid of pressure in the inlet tract before the throttle body to extend turbo life and keeps the wheel speed up between shifts on a manual trans car. Since we don't have manual trans that is not an issue. After many years we don't see many turbo fail due to NOT having a valve so for most guys it is not a good investment. I willl not make the car faster and might not extend the life of the turbo. If it make you feel better to have one go for it won't hurt likely won't help though either.
Mike Licht
Mike Licht
Originally posted by azgn
Manuel is prolly running 40 lbs of boost thru two turbos....I imagine he needs a BOV or two
just because he needs 'em doesn't mean the average TR does
not exactly relevant to most folks
22 psig at Las Vegas. Not that it matters. He is going to be upping it to 30+. When, I do not know.
I sell the Greddy Type-R BOV with flange for under $240. Do you need it? Well, that is really up to you. It will not add any performance to your TR. It will however reduce the pressurized air built up when you shut the throttle.
For all of the people that say you are not on and off the throttle very much, do you actually drive your TR? I would be willing to bet that you are on and off the throttle a lot more than you think. Expecially if you are in stop and go traffic (not bumper to bumper).
There are people that are going to be against the BOV no matter what. If you want the piece of mind that you are minimizing the turbo slam, then get it. If not, then do not purchase one.
For all of the people that say you are not on and off the throttle very much, do you actually drive your TR? I would be willing to bet that you are on and off the throttle a lot more than you think. Expecially if you are in stop and go traffic (not bumper to bumper).
There are people that are going to be against the BOV no matter what. If you want the piece of mind that you are minimizing the turbo slam, then get it. If not, then do not purchase one.
Vendor Defendor
Out the window
- Joined
- Nov 25, 2002
No way in hell would I ever put something on my car that has 'Type-R' in the name; no matter how good it is. I dont care how ignorant I sound.
david buschur
New Member
- Joined
- Mar 14, 2004
I see this is more opinion that anything else and as usual on the internet giving an opinion does little. Still I am going to type my ass off.
I own a decent sized shop that has specialized in turbocharged DSM's (Talons, Eclipses, Lasers, Galant VR-4's and the EVO8) for about 15 years now.
I have tried and sold just about every blow off valve/compressor bypass valve there is.
The first generation DSM's come with a really good valve, as a matter of fact there aren't too many aftermarket valves that perform the duty they are suppose to any better.
The valve as you know is suppose to open when you lift off the throttle to allow the boost pressure in the intercooler pipe to be released (either into the atmosphere or re-circulated back into the MAS pipe) and not stall the turbo. The woo woo woo sound you hear when you get off the gas is the air bouncing back and forth from the compressor wheel to the closed throttle plate, this causes the compressor wheel to try and stop.
We tried a few valves on my fathers WE4 quite a few years ago. It worked well and did what it was supppose to. No gain in HP, ET or trap speed as it is not going to do any for performance on an automatic car. It did cause driveability problems. We had it vented to atmosphere, what happens is the MAS measures the air that is coming through it. When you lift off the gas the air that was measured is not dumped into the atmosphere throwing the air fuel mixture off. Same thing happens if you have a valve that leaks slightly at idle, as does the DSM valve.
Here's more useless information. The way to fix this is if you are going to run a MAS on your Buick and a BOV then simply put a nipple on your MAS pipe and route the air back into the system after the BOV releases it.
On a speed density car the lost air from venting it to atmosphere has no effect at all.
More information Most aftermarket valves have an adjustment on the top of them. They also come with different rate springs. The adjustment and spring rates will effect how the valve opens when you snap off the throttle. IF the spring is too heavy or the adjustment too tight it will not open at all or enough. In this case you still get compressor surge. On the same note if you get a spring that is light enough and don't tighten down the adjustment bolt so it does work properly then you end up with either a leak at idle (fine if speed density or routed back in) or you get a leak at high boost pressures.
Ron's car (Rapid Automotive) that I race is Ken Duttweiller's old car. Ken built the car, it made 1485 hp. The car has two expensive turbos on it. The same turbos are on the car now as when Ron got it, NO BOV's. My tube chassis DSM runs 7.8's at 175 mph, NO BOV's. Both these cars are automatics.
After realizing that BOV's either leak or don't work as they should when they aren't leaking I have pretty much deleted them from everything I own. This includes some high HP 5 speed manual trans cars.
I have not personally seen a turbo fail from not having one. Maybe back in the old days when aftermarket turbos weren't what they are today they did.
My advise, especially on a Buick. Save your money and don't buy one. IF you do decide to buy one, call us I'll give you a good deal on anyone you want! haha
Take care,
David Buschur
www.buschurracing.com
I own a decent sized shop that has specialized in turbocharged DSM's (Talons, Eclipses, Lasers, Galant VR-4's and the EVO8) for about 15 years now.
I have tried and sold just about every blow off valve/compressor bypass valve there is.
The first generation DSM's come with a really good valve, as a matter of fact there aren't too many aftermarket valves that perform the duty they are suppose to any better.
The valve as you know is suppose to open when you lift off the throttle to allow the boost pressure in the intercooler pipe to be released (either into the atmosphere or re-circulated back into the MAS pipe) and not stall the turbo. The woo woo woo sound you hear when you get off the gas is the air bouncing back and forth from the compressor wheel to the closed throttle plate, this causes the compressor wheel to try and stop.
We tried a few valves on my fathers WE4 quite a few years ago. It worked well and did what it was supppose to. No gain in HP, ET or trap speed as it is not going to do any for performance on an automatic car. It did cause driveability problems. We had it vented to atmosphere, what happens is the MAS measures the air that is coming through it. When you lift off the gas the air that was measured is not dumped into the atmosphere throwing the air fuel mixture off. Same thing happens if you have a valve that leaks slightly at idle, as does the DSM valve.
Here's more useless information. The way to fix this is if you are going to run a MAS on your Buick and a BOV then simply put a nipple on your MAS pipe and route the air back into the system after the BOV releases it.
On a speed density car the lost air from venting it to atmosphere has no effect at all.
More information
Most aftermarket valves have an adjustment on the top of them. They also come with different rate springs. The adjustment and spring rates will effect how the valve opens when you snap off the throttle. IF the spring is too heavy or the adjustment too tight it will not open at all or enough. In this case you still get compressor surge. On the same note if you get a spring that is light enough and don't tighten down the adjustment bolt so it does work properly then you end up with either a leak at idle (fine if speed density or routed back in) or you get a leak at high boost pressures.Ron's car (Rapid Automotive) that I race is Ken Duttweiller's old car. Ken built the car, it made 1485 hp. The car has two expensive turbos on it. The same turbos are on the car now as when Ron got it, NO BOV's. My tube chassis DSM runs 7.8's at 175 mph, NO BOV's. Both these cars are automatics.
After realizing that BOV's either leak or don't work as they should when they aren't leaking I have pretty much deleted them from everything I own. This includes some high HP 5 speed manual trans cars.
I have not personally seen a turbo fail from not having one. Maybe back in the old days when aftermarket turbos weren't what they are today they did.
My advise, especially on a Buick. Save your money and don't buy one. IF you do decide to buy one, call us I'll give you a good deal on anyone you want! haha
Take care,
David Buschur
www.buschurracing.com
Hopefully w/out getting in trouble here can I ask a couple of questions? Why were blow off valves ever invented? I know you said not nesc. on automatic cars, but I drive my car every day rain or shine and in stop and go traffic. I hear the flock of turkeys at least 10-20 times a day on regular driving and even on half throttle let-ups. So how much is bad on a turbo? I mean there can't be no point where they are usefull or is it only with down-spoolling between shifts on manual transmissions and for performance and not a longevity issue? As far as being a waste of money aren't there a LOT of things we all buy for our cars that could be considered a waste of money? Any wheel that isn't the lightest available could be considered a waste of money and a detriment to performance. I mean wasting money is what my car is all about
Just curious.
Adum
Just curious.
Adum
GNVYUS 1
Well-Known Member
- Joined
- Dec 15, 2002
I have yet to hear or read about an aftermarket turbo on a GN go past 40k without needing a touch up due to shaft play. My first Ta49 lasted only 2 years with tons of ONLY 15 psi runs everyday on the street.
Aftermarket turbos are bigger, get beat on more, and live less than half the life of the stocker. This is (probably) because the stocker has way less cfm coming back at it to try to spin the wheel backwards after a hard run.
I know, read, and heard about more GN guys that have gone through aftermarket turbos with shaft play than ANY of the DSM guys I know, read or heard with blow offs. Oil contamination aside on rebuilds.
Supra automatics run blow offs and run on average larger turbos. Yet they still do not have the frequent shaft play problems we do after a few years running higher psi daily.
Buschur, how many aftermarket DSM turbos have come back with shaft play compared to GN's, oil contamination not included?
Aftermarket turbos are bigger, get beat on more, and live less than half the life of the stocker. This is (probably) because the stocker has way less cfm coming back at it to try to spin the wheel backwards after a hard run.
I know, read, and heard about more GN guys that have gone through aftermarket turbos with shaft play than ANY of the DSM guys I know, read or heard with blow offs. Oil contamination aside on rebuilds.
Supra automatics run blow offs and run on average larger turbos. Yet they still do not have the frequent shaft play problems we do after a few years running higher psi daily.
Buschur, how many aftermarket DSM turbos have come back with shaft play compared to GN's, oil contamination not included?
david buschur
New Member
- Joined
- Mar 14, 2004
How many DSM turbo's have come back with shaft play compared to Buick's? That was the question.
I can't answer that to be honest. I don't sell Buick turbos on a daily or even monthly basis. I can only speak from what myself, my father and maybe the tube car that I drive for Ron Luman has seen.
Non of us have had a turbo go bad on our Buicks for any reason with the exception of one my father ate that was from oil contamination. I know one of my dad's turbo Buicks has over 95,000 miles and still has the stock turbo on it. That car has been beat to death.
As for the DSM turbos the story is the same. I have never had one that I sent back for customer warranty job that failed from anything but oil contamination.
We have deleted the BOV on the 5 speed manual trans race cars we build and the automatic race cars we build, I haven't had any of those turbos fail.
I hear the surge on my Buick everytime I drive it. I have a PT52 on the car. I like hearing it. It is a big joke at the GS Nationals, everytime my dad and I hear it we say, "HEY MO!" Like the three stooges, when Curly us to say, "woo woo woo woo, HEY MO!"
(I think I'm hilarious, just incase you are all wondering! haha)
Bottom line is if you are worried about the turbo being ruined from surge get a valve. I explained the issues you may have with the MAS and leaks and such, watch for those. We have the 1st generation BOV's from the DSM's for I think $100, the flange is $45 in stainless with a stainless fish mouth piece of tube so you can weld it on. I guess it isn't a bunch of money, we have all wasted more than that on parts that did less.
Take care,
David Buschur
www.buschurracing.com
I can't answer that to be honest. I don't sell Buick turbos on a daily or even monthly basis. I can only speak from what myself, my father and maybe the tube car that I drive for Ron Luman has seen.
Non of us have had a turbo go bad on our Buicks for any reason with the exception of one my father ate that was from oil contamination. I know one of my dad's turbo Buicks has over 95,000 miles and still has the stock turbo on it. That car has been beat to death.
As for the DSM turbos the story is the same. I have never had one that I sent back for customer warranty job that failed from anything but oil contamination.
We have deleted the BOV on the 5 speed manual trans race cars we build and the automatic race cars we build, I haven't had any of those turbos fail.
I hear the surge on my Buick everytime I drive it. I have a PT52 on the car. I like hearing it. It is a big joke at the GS Nationals, everytime my dad and I hear it we say, "HEY MO!" Like the three stooges, when Curly us to say, "woo woo woo woo, HEY MO!"
(I think I'm hilarious, just incase you are all wondering! haha)
Bottom line is if you are worried about the turbo being ruined from surge get a valve. I explained the issues you may have with the MAS and leaks and such, watch for those. We have the 1st generation BOV's from the DSM's for I think $100, the flange is $45 in stainless with a stainless fish mouth piece of tube so you can weld it on. I guess it isn't a bunch of money, we have all wasted more than that on parts that did less.
Take care,
David Buschur
www.buschurracing.com
turbo buicks
ESADAH!!!
- Joined
- Jun 13, 2002
I RUN A GREDDY TYPE-R. NO PROBS. HEAVY SPRING. UNDER 5 PSI IT DOESNT DO MUCH BUT STILL OPENS. ABOVE 10 PSI IT REALLY BLOWS, LOL. THATS THE POINT WHERE I FEEL ITS MOST NEEDED, ABOVE 10 PSI. GOT IT FOR CHRISTMAS BTW. HEY VENDOR, I GOT A 8 SEC STAGE 2 GN TYPE-R I WAS LOOKIN TO GIVE AWAY BUT NEVER MIND NOW
I tested the HKS ssqv and it does not leak one bit. It is a pull type valve so more boost equals a tighter seal. I bench tested it mounted to the pipe. With the spring set tight it will do a good shot as soon as the boost drops a few psi on the nipple. It seems like it can be set up for different levels. I'm hoping to just dump the shock going back to the Turbo. I think I will be able to get it to be able to do a quick dump so the turbo doesn't surge but at the same time I don't get black smoke or driveability concerns. Like we all know, the truth is in the road test. I am very happy that it doesn't leak. Hopefully it won't do a huge dump on a slight throttle lift. If it does the car will probably $hit all over itself for a second or two. We'll see!
V6UnderPressure
The Artist FKA Scott4DMny
- Joined
- May 27, 2001
There you go GNX. Theres your answer on why you need it. If your car is track only, you wouldnt need it. But a Street Driver WILL benefit GREATLY. Think if your up to 18 psi and then have to immediatly brake for traffic or something. That 18psi is forced back against the compressor. GET ONE for your exact posted reason is your perfect reason.
Scott
Scott
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