WHICH DUMP VALVE?
18 November 2004, 12:03 AM
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WHICH DUMP VALVE?
WHICH IS THE BEST DUMP VALVE TO GO FOR?
I'VE BEEN ADVISED BY TSL THAT THE TURBOSMART ONE IS THE BEST........CAN ANYONE TELL ME ANY DIFFERENT?
DOES ANYONE HAVE A TURBOSMART BOV FITTED?
I'VE BEEN ADVISED BY TSL THAT THE TURBOSMART ONE IS THE BEST........CAN ANYONE TELL ME ANY DIFFERENT?
DOES ANYONE HAVE A TURBOSMART BOV FITTED?
18 November 2004, 06:16 AM
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As Greasemonkey no longer seems to be posting, let me help you 
FIRST THERE IS NO NEED TO SHOUT!
Second, I guess you know your car has a dump valve as standard? If your car is running standard boost then the standard dump valve is perfectly adequate.
If you are determined to spend some money then there are two types of dump valve you can buy, recirc(ulating) and VTA (Vent to Atmosphere). The first may be described as the connoisseur's choice. The latter would be more the boy racer's choice, all noise and no performance. It will have an adverse effect on performance to a greater or lesser degree. You will notice a hesitation on planting your right foot again having lifted off.
It may be possible to remap your ECU to reduce or eliminate that hesitation, but that's a lot of expense for just a loud psssooo sound.
FIRST THERE IS NO NEED TO SHOUT!
Second, I guess you know your car has a dump valve as standard? If your car is running standard boost then the standard dump valve is perfectly adequate.
If you are determined to spend some money then there are two types of dump valve you can buy, recirc(ulating) and VTA (Vent to Atmosphere). The first may be described as the connoisseur's choice. The latter would be more the boy racer's choice, all noise and no performance. It will have an adverse effect on performance to a greater or lesser degree. You will notice a hesitation on planting your right foot again having lifted off.
It may be possible to remap your ECU to reduce or eliminate that hesitation, but that's a lot of expense for just a loud psssooo sound.
18 November 2004, 08:16 AM
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The Turbosmart is both a recircilated and atmospheric dumpvalve. When you drive normally the BOV wents recir. but when you step on the gas and the throttle opens the BOV wents to the atmosphere.
I have looked at the Turbosmart also but found a APS dump valve for near half the price that works the same.
I have heard that the Turbosmart bov won prices around the world for it´s design.
I have looked at the Turbosmart also but found a APS dump valve for near half the price that works the same.
I have heard that the Turbosmart bov won prices around the world for it´s design.
18 November 2004, 01:36 PM
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Originally Posted by Brit_in_Japan
As Greasemonkey no longer seems to be posting, let me help you
FIRST THERE IS NO NEED TO SHOUT!
Second, I guess you know your car has a dump valve as standard? If your car is running standard boost then the standard dump valve is perfectly adequate.
If you are determined to spend some money then there are two types of dump valve you can buy, recirc(ulating) and VTA (Vent to Atmosphere). The first may be described as the connoisseur's choice. The latter would be more the boy racer's choice, all noise and no performance. It will have an adverse effect on performance to a greater or lesser degree. You will notice a hesitation on planting your right foot again having lifted off.
It may be possible to remap your ECU to reduce or eliminate that hesitation, but that's a lot of expense for just a loud psssooo sound.
FIRST THERE IS NO NEED TO SHOUT!
Second, I guess you know your car has a dump valve as standard? If your car is running standard boost then the standard dump valve is perfectly adequate.
If you are determined to spend some money then there are two types of dump valve you can buy, recirc(ulating) and VTA (Vent to Atmosphere). The first may be described as the connoisseur's choice. The latter would be more the boy racer's choice, all noise and no performance. It will have an adverse effect on performance to a greater or lesser degree. You will notice a hesitation on planting your right foot again having lifted off.
It may be possible to remap your ECU to reduce or eliminate that hesitation, but that's a lot of expense for just a loud psssooo sound.
18 November 2004, 03:17 PM
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A VTA dump valve exhausts intake air (i.e. before combustion) to atmosphere. The ECU has calculated the amount of fuel required for optimum combustion based on the amount of air it measures coming into the engine. If you vent some of that air to atmosphere then the calculation will be wrong and your mixture will be rich (too much fuel). That means less than optimum combustion and less power, albeit for just a small period of time.
Unless you have had you ECU reprogrammed to compensate you will get some form of hesitation, large, small or maybe hardly noticable. But it cannot improve the performance of the engine. In fact removing the dump valve altogether and blanking it off with give you the best response when you put your foot down again as there is still high pressure air in the inlet side of the engine, the only problem with that is you will significantly shorten the life of your turbo.
This has been debated many times. I suggest you do a search on Dump Valves and BOV's and read some of the threads (try a search for threads contributed to by greasmonkey, you should find a good few to choose from). The standard recirc dump valves appears top be very well suited to standard engines. If you are running incresed boost then a higher spec recirc dump valve would be better to maintain boost without leaking.
A number of people have said the best performance mod they've done was to remove their aftermarket VTA dump valve and refit a standard item.
Unless you have had you ECU reprogrammed to compensate you will get some form of hesitation, large, small or maybe hardly noticable. But it cannot improve the performance of the engine. In fact removing the dump valve altogether and blanking it off with give you the best response when you put your foot down again as there is still high pressure air in the inlet side of the engine, the only problem with that is you will significantly shorten the life of your turbo.
This has been debated many times. I suggest you do a search on Dump Valves and BOV's and read some of the threads (try a search for threads contributed to by greasmonkey, you should find a good few to choose from). The standard recirc dump valves appears top be very well suited to standard engines. If you are running incresed boost then a higher spec recirc dump valve would be better to maintain boost without leaking.
A number of people have said the best performance mod they've done was to remove their aftermarket VTA dump valve and refit a standard item.
18 November 2004, 04:14 PM
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Partly true - in my case the mixture is a wee bit rich - hence the pops and bangs from the exhaust but i havent noticed ANY difference in performance. My car is a jap import so perhaps the ecu is already uprated? Im not saying your wrong in what your saying and you certainly have a lot of technical info to back it up but not all dv's are bad news - not on my car anyway. You, like many people on this forum seem to HATE dump valves and are so quick to slate someone for buying one. At the end of the day its each man to his own so herbie - if you want a dv then get one. Tsl know their stuff and i doubt they would sell a product which is bad for your engine. Cheers.
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18 November 2004, 04:22 PM
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I don't "HATE" dump valves, but if someone is fitting a VTA dump valve in the belief it will somehow improve their engine then I think it's fair they should be made aware that there are potentially some down sides and no upsides unless the sound is the main motivation. If you haven't noticed any difference in performance then I'm pleased for you.
For the record my car has a HKS SSQV VTA dump valve. It was on the car when I bought it. Initially I thought it was great, you know, makes it sound more like a rally car. But in truth I've grown tired of the noise and I don't like the very noticeable hesitation I get after it "dumps". I would prefer a better throttle response. I have a standard dump valve to fit back onto it, just need the time to do it.
For the record my car has a HKS SSQV VTA dump valve. It was on the car when I bought it. Initially I thought it was great, you know, makes it sound more like a rally car. But in truth I've grown tired of the noise and I don't like the very noticeable hesitation I get after it "dumps". I would prefer a better throttle response. I have a standard dump valve to fit back onto it, just need the time to do it.
18 November 2004, 04:43 PM
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I've got an HKS SSQV too. Its actually my 2nd as I had one on my old GTIR and loved it. I'm well aware that it does nothing performance wise and I have to say I'm not sure I noticed much in the way of a negative when fitting it although I'm considering fitting the stock unit back on to test if there is much difference.
It won't sound like a rally car becuase rally cars don't have DVs anyway apparently. The chirping noise is compressor surge and I'll leave it to someone more knowledgeable than I to explain that nugget of information - I don't see why its good thing not to have a DV and have compressor surge on a rally car.
Just for the noise factor I'd like an induction kit too but thats yet another bag of spanners!
It won't sound like a rally car becuase rally cars don't have DVs anyway apparently. The chirping noise is compressor surge and I'll leave it to someone more knowledgeable than I to explain that nugget of information - I don't see why its good thing not to have a DV and have compressor surge on a rally car.
Just for the noise factor I'd like an induction kit too but thats yet another bag of spanners!
18 November 2004, 05:29 PM
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Brit - where does it say he wants it for performance??
And anyway why should you tell him the downsides - who are you? the dump valve police??! Im sorry for going off on one but im f**king sick of people saying that dv's are only for chavs or boy racers - thats such bullsh£t!!! led washer jets or neons = definatley chav material.
Happy trails....
And anyway why should you tell him the downsides - who are you? the dump valve police??! Im sorry for going off on one but im f**king sick of people saying that dv's are only for chavs or boy racers - thats such bullsh£t!!! led washer jets or neons = definatley chav material.
Happy trails....
18 November 2004, 07:10 PM
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there seems to be alot of people who slate VTA dump valves, not only on here but on scoobynet as well.........i'm starting to think about leaving them alone. I only wanted it for the nice sound anyway! (and i'm not a boy racer either!!).
i know that i won't get improved performance but i didn't realise that they could cause problems with the fuel/air mixture.
i know that i won't get improved performance but i didn't realise that they could cause problems with the fuel/air mixture.
18 November 2004, 11:39 PM
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there seems to be alot of people who slate VTA dump valves, not only on here but on scoobynet as well
Hmm, sorry mate but I have to disagree - I run a Forge VTA dumper on my ra and it has no adverse effects at all - in fact it feel a touch less laggy than before???
Followed by
i havent noticed ANY difference in performance
And anyway why should you tell him the downsides - who are you? the dump valve police??!
Brit is simply trying to help Herbie make an informed decision and you slate him for it. His advice has been sound.
Yours - a little . . . . . .biased/emotional/defensive?!
Can't believe I was drawn in.
Going back to sit in the nosebleeds with Brun.
19 November 2004, 12:49 AM
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Originally Posted by herbie77
there seems to be alot of people who slate VTA dump valves, not only on here but on scoobynet as well.........i'm starting to think about leaving them alone. I only wanted it for the nice sound anyway! (and i'm not a boy racer either!!).
i know that i won't get improved performance but i didn't realise that they could cause problems with the fuel/air mixture.
i know that i won't get improved performance but i didn't realise that they could cause problems with the fuel/air mixture.
Originally Posted by STI-R/A
Brit - where does it say he wants it for performance??
You know there are people who actually think fitting a VTA dump valve is a performance mod. If I've helped correct that misimpression for even one scoobynetter reading this thread then my work is done
19 November 2004, 07:47 AM
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I run a td05 at 1.35bar on the std. dump valve.
still holding up well.
unfortunately, by having an induction kit, the recirc dv makes noise a la vta (but to a lesser degree thank God).
its a pure bling mod, no benefit to the engine or performance as mentioned.
still holding up well.
unfortunately, by having an induction kit, the recirc dv makes noise a la vta (but to a lesser degree thank God).
its a pure bling mod, no benefit to the engine or performance as mentioned.
19 November 2004, 10:39 AM
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Originally Posted by STI-R/A
Edd dont you know induction kits are only for chavs!!!! (not)
"Pass me my burbery cap"
"Which one is it?"
"The one that says Bad **** on it!"
/Samuel L Jackson chav mode off
19 November 2004, 11:09 AM
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Originally Posted by STI-R/A
7foot - Sorry i meant to say i havent noticed any NEGATIVE effects!!!
You will actually have negative effects, you wont see them though unless you have the above fitted.
A vta isnt good on a scoob, full stop, unless the car is mapped for it.
You say you have seen the car go rich? well whats the opposite? because your car will do that as it over compensates, not knowingly, but due to the way the vta works, so very rich one way, very lean the other.
Me, i dont need any vta dv, they are a waste of time and money, the way my scoob works, the vta has no advantage, if anything it will give me lag, especially on fast gear changes.
Tony
19 November 2004, 11:27 AM
#25
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I've got a knocklink - car is MY00 UK turbo full de-cat, K&N panel and TEK2. Only ever get one light on (and have checked all lights work btw) every now and again.
Am I right in saying the car runs rich becuase the ECU thinks theres more air going in than actual becuase the dumped air is expected back in the inlet. As its not dumped back into the inlet but VTA'd the ratio of air to fuel is out becuase theres less air than actually expected. The AFR gauge reads a fair way into the green over 5PSI but other than that I'm not too sure what else its telling me
Didn't think this was too bad a thing to happen? In what way would a VTA lean the car out if at all?
Not meaning to add to the argument I actually want to know how bad if at all it is to run a VTA. I like the whooshy sounds an induction kit makes but have stayed with a panel due to MAF failure fears so if the VTA is going to do damage over the long term I'd quite happily take it off - even if I do like the sound.
Am I right in saying the car runs rich becuase the ECU thinks theres more air going in than actual becuase the dumped air is expected back in the inlet. As its not dumped back into the inlet but VTA'd the ratio of air to fuel is out becuase theres less air than actually expected. The AFR gauge reads a fair way into the green over 5PSI but other than that I'm not too sure what else its telling me
Didn't think this was too bad a thing to happen? In what way would a VTA lean the car out if at all?
Not meaning to add to the argument I actually want to know how bad if at all it is to run a VTA. I like the whooshy sounds an induction kit makes but have stayed with a panel due to MAF failure fears so if the VTA is going to do damage over the long term I'd quite happily take it off - even if I do like the sound.
19 November 2004, 12:47 PM
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19 November 2004, 12:50 PM
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BRD wont sell you one. Nuff said
If you have a link ECU that's not using the MAF then its a lot more ideal. The standard DV is fine, as is the uprated Forge recirc but you have to question why you need it.
If you want it for the noise, that's your choice.
MB
If you have a link ECU that's not using the MAF then its a lot more ideal. The standard DV is fine, as is the uprated Forge recirc but you have to question why you need it.
If you want it for the noise, that's your choice.
MB
19 November 2004, 01:22 PM
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This is just my opinion:
VTA can make the car run rich, causing fuel to pop and bang in the exhaust. Shis sounds great but not sure if this is good for your engine.
VTA also makes a venting noise which is also a reason to but one.
One my car however, no matter how much I adjusted them I could not get them to let my car run properly. It made my car run very jerky especially at slow speeds when you are trying to cruise along normally. I have tried a Forge and a Blitz VTA and I'm running standard boost, I went straight back to the standard one.
My mate who has a 300BHP+ RB5 has tried 6 different VTA valves, he had the same issues and has went back to the standard one.
However, some cars seem to manage okay with them??
VTA can make the car run rich, causing fuel to pop and bang in the exhaust. Shis sounds great but not sure if this is good for your engine.
VTA also makes a venting noise which is also a reason to but one.
One my car however, no matter how much I adjusted them I could not get them to let my car run properly. It made my car run very jerky especially at slow speeds when you are trying to cruise along normally. I have tried a Forge and a Blitz VTA and I'm running standard boost, I went straight back to the standard one.
My mate who has a 300BHP+ RB5 has tried 6 different VTA valves, he had the same issues and has went back to the standard one.
However, some cars seem to manage okay with them??
19 November 2004, 01:27 PM
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Agreed, when I had one a few years back, the car was quite jerky on and off the throttle, no matter what spring / spacers I used. This was a bit of a pain in the *** on roundabouts etc...
I think to sum up, there's quite a lot of side issues just for a hissing noise.
MB
I think to sum up, there's quite a lot of side issues just for a hissing noise.
MB