Question about Blow Off Valve!

[Invincible]

Hello,
Sorry if this is a repost but i need some experts to shed light on this please.
I drive a Leon Cupra, which i bought brand new and then went and installed an HKS SSQV 2 Blow off valve with the proper adapters to make it fit to the car, all of which was done at an excellent Auto garage who are professional at this, the car had around 5000 kms when it was fitted and now recently dealership is voiding the warranty on any car that has an aftermarket Blow off valve on, so i went and removed mine before my 70k service which is due tomorrow.
Now my question is, i've been reading on the internet that Atmospheric Blow off valve such as the one i have can shorten the life of an engine or cause serious damages in some cases, especially on VAG car and i cant seem to understand as to why! I would like to put my BOV back on right after the service because the difference it makes to the car is awesome, having put the stock one back i can feel the car takes much longer to boost up, especially on the lower end of the rev range, while with the HKS BOV the car was a joy to drive, not to mention that fuel consumption has somehow gone up a bit. Plus i like the sound it makes

Thanks

 

[Invincible]

Anyone?!!

 

[Donnyboy]

Is it possible the original valve is ripped? There is a newer revision valve now without the diaphragm.

http://www.jkm.org.uk/performance/M...FSI-images/Overviewpage/Divert/NewDV1_big.jpg

 

[Invincible]

No the original valve is fine, I know about the Rev D valve but I love the sound of the HKS and it was pricey to buy so just want to know if it harms the engine n weather I should keep it or not!

 

[RobDon]

Basically venting to atmosphere is bad for your engine because the MAF measures the airflow and the ECU fires the injectors based on this amount of air. By venting to atmosphere you're reducing the air but the ECU doesn't know this so too much fuel enters the engine. This rich condition can damage the CAT, can cause bore wash (excess fuel washing away the oil in the bores causing excessive piston ring wear), foul spark plugs, etc. etc. eventually causing engine failure.

 

[Invincible]

Now what I don't understand here is; the air is released to atmosphere after I've already lifted off and tgerefore no excess fuel and the car running rich, and if that's the case then why is the performance much improved with the blow off valve as well as fuel consumption?

 

[RobDon]

As soon as you vent to atmosphere you are running rich because the engine has measured that air and is expecting it to enter the engine. It will deliver too much fuel every time you vent. You may think it is not causing any problems but internally it is.

 

[Invincible]

Hmmm thanks alot for the input, I might go and but the Rev D because the stock one just sucks!

 

[boroboy19]

Hi Guys,
sorry to interrupt...I am interested in installing a dump valve on my Cupra. Can anyone point me to a good one that improves the performance but overall makes a nice sound! But to gain this I don't want to harm the engine.

Thanks

 

[Blade]

Simples,

Fit the revision D and get a quality CAI.

 

[dmkay_80]

Basically venting to atmosphere is bad for your engine because the MAF measures the airflow and the ECU fires the injectors based on this amount of air. By venting to atmosphere you're reducing the air but the ECU doesn't know this so too much fuel enters the engine. This rich condition can damage the CAT, can cause bore wash (excess fuel washing away the oil in the bores causing excessive piston ring wear), foul spark plugs, etc. etc. eventually causing engine failure.

Im confused by this.
How does the MAF measure air from the DV when it enters the intake after the MAF?
Or am I just being blonde lol

 

[cupra.al]

maf sends the message to the ecu how much air is going in then a small amount enough to make a difference gets dumped to atmosphere after the maf but the ecu is still telling the injectors to send the same amount of fuel even though theres less air making it run rich.

ive just said what robdon has but made it more simple to understand hopefully.

 

[dmkay_80]

Ive just realised i was being very blonde lol.
Any air that comes from DV has already been through the MAF.

 

[cheungy]

Hmmm thanks alot for the input, I might go and but the Rev D because the stock one just sucks!

If you want the WOOSH WOOSH noise just put the "forge" spacer on for the fraction of the price you paid for the HKS SQV whatever valve... Sound is defin nice from the HKS but its not very good for the engine from what I read from the golf forums. Hardly anyone in the UK is using one these on teh TFSi engine purely its stupid money I think the last time I saw one for sale is 200 quid (aleast) heck my spacer was only 30 and the rev D = 40 more less? but yea hope the info helps.

 

[CupraLee K1]

If you want the WOOSH WOOSH noise just put the "forge" spacer on for the fraction of the price you paid for the HKS SQV whatever valve... Sound is defin nice from the HKS but its not very good for the engine from what I read from the golf forums. Hardly anyone in the UK is using one these on teh TFSi engine purely its stupid money I think the last time I saw one for sale is 200 quid (aleast) heck my spacer was only 30 and the rev D = 40 more less? but yea hope the info helps.

Just got the Forge Spacer on mine

 

[boroboy19]

hi Dave.c - so in your opinion the REV D is the right one?

REVd - jkm.org.uk/performance/Misc/Misc_Performance_pictures/TFSI-images/Overviewpage/Divert/NewDV1_big.jpg

the website says about spacer...does this mean that you need an extra part? can you point me to which one it is?

Is this easy to do it yourself? cheers

 

[CupraLee K1]

hi Dave.c - so in your opinion the REV D is the right one?

REVd - jkm.org.uk/performance/Misc/Misc_Performance_pictures/TFSI-images/Overviewpage/Divert/NewDV1_big.jpg

the website says about spacer...does this mean that you need an extra part? can you point me to which one it is?

Is this easy to do it yourself? cheers

Spacer is here Clicky Clicky

Need to scroll down to Item: FMDV14T

Just need to unbolt standard DV, screw in spacer and put standard DV back on top.

Can be a bit fiddly with the engine cover in the way (can always take it off)

 

[cheungy]

hi Dave.c - so in your opinion the REV D is the right one?

REVd - jkm.org.uk/performance/Misc/Misc_Performance_pictures/TFSI-images/Overviewpage/Divert/NewDV1_big.jpg

the website says about spacer...does this mean that you need an extra part? can you point me to which one it is?

Is this easy to do it yourself? cheers

Depends on your Car, If your a lucky one with a Cupra then its easy as its relocated to the front of the engine bay.

However its the TFSI sport or FR even it will be located under the car, either get a garage to fit it for you within 30mins (easier way!) or do it yourself however i would advise to get the garage to save you the time and grief.

The car would already have a have a divertor valve its just optional if you want to change it for the latest oem one which is REV D (piston instead of diaphram which are likely to tear due to the heat from the turbo) AND as a ADDON you can have the forge spacer fitted at the same time to give the wooshing noise. *this will get louder and sharper after remap when the turbo boost is kicked up.

Hope this helps > I can do the divertor valve job in 30mins, Took me over 3-4 hours first time i tried sob sob

 

[Invincible]

Well then again by fitting a Spacer you are venting the air into atmosphere and therefore the same issue as having an HKS SSQV2 BOV isn't it?!!

 

[CupraLee K1]

Well then again by fitting a Spacer you are venting the air into atmosphere and therefore the same issue as having an HKS SSQV2 BOV isn't it?!!

Quote from Forge on JKM Product Listing for Spacer:

"Yet another first for the Volkswagen and Audi Tuning Market from Forge !
Forge have developed a Patented Atmospheric Blow-Off adapter specifically designed to fit the TFSI and TSI engine. Simple in execution, yet offering the desirable atmospheric blow-off valve sound, this product has been designed to be fully compatible with the Bosch engine management systems employed.
This is not only a replacement for vehicles fitted with the new OEM solenoid valve as listed below, but will also fit earlier 2.0 FSiT applications."