Tdi Bov

[Joe TDI]

www.youtube.com/watch?v=rzhADMFfJSE

A lot of people in Europe seem to be doing this to their TDI's.

I am well aware that a BOV has no place on a TDI because diesels have no throttle plate so why do people do it?

 

[TDIMeister]

Man, that sounds fricken dumb.

 

[Joe TDI]

Hmm...........

 

[TurbinePower]

Man, that sounds fricken dumb.

Indeed. It's possible that such a thing is stupid enough to equal the idiocy put on parade in the comments of such videos through atrocious grammar and even an even more horrific disdain for anything remotely resembling proper spelling.

I don't think I'll ever understand the fascination folks have with that stupid little air release sound. It's noisy, and nothing more.

 

[vwmikel]

It kind of reminds me of this:

http://www.youtube.com/watch?v=Nnzw_i4YmKk

It serves about as much purpose.

 

[TDIMeister]

It starts at infancy when babies are drawn to noise makers and little things that rattle.

 

[Toby]

It kind of reminds me of this:

http://www.youtube.com/watch?v=Nnzw_i4YmKk

It serves about as much purpose.

You've got to be kidding me, that is the most stupid thing I have ever seen

 

[sabrewolf]

Bub Rub Says Woot Woot!!!

 

[gjetta]

wooooooo woooooooooohhh lmao

 

[crazyrunner33]

LOL, I bought one of those as a joke and put it in my neighbors exhaust pipe, sad this was he actually liked it.

 

[grtn316]

I hate to "go against the grain" (as I'm with you guys when you say Diesels don't need BOVs) but I have noticed that my TDI is getting compressor surge for some reason. Coming for the turbo'd gasoline world, I know a BOV would solve this problem however, before I attempt something that everyone considers dumb (for valid reasons) maybe you guys have some ideas about the problem...

Diesels may not have a throttle plate but when you go from full throttle to no throttle and you have 20psi(ish) sitting in the pipes, it has to go somewhere fast...and on my car, I've noticed its pushing back through the turbo...which is very bad for the turbo.

Thoughts?

 

[bmwvw]

It kind of reminds me of this:

http://www.youtube.com/watch?v=Nnzw_i4YmKk

It serves about as much purpose.

Thats the single greatest thing in the world

 

[bencarr23]

I know this is considered a no no. but when i get on it and let off anywhere above 22 psi i get a loud wamp wamp from the air comming out my CAI. People at the dyno day will get a chance to hear this on the test drives.

 

[grtn316]

I know this is considered a no no. but when i get on it and let off anywhere above 22 psi i get a loud wamp wamp from the air comming out my CAI. People at the dyno day will get a chance to hear this on the test drives.

Same thing here. That's compressor surge. VERY bad for your seals inside the turbo. Each time this happens the life of you turbo is shortened. This can also create excess oil in your intercooler pipes (leaking past oil seals in turbo).

 

[TDIMeister]

What do you guys define as "surge"?

 

[grtn316]

What do you guys define as "surge"?

Surge is when you have x amount of pressure built up and no where to go but the place of least resistant...the turbo.

The air is pushed back through the compressor housings on the turbo and it will either exit out of the air filter or pop off the stock intake tube from the turbo.

Ask any turbo rebuilder and they will tell you backpresure like this is unhealthy for your turbo.

Having an excess amount of oil in your intake system is NOT normal. This is a results of compressor surge pushing on the seals and oil leaking past them.

 

[TDIMeister]

And with no throttle plate in a Diesel, where is this pressure build-up happening?

 

[bmwvw]

Surge is when you have x amount of pressure built up and no where to go but the place of least resistant...the turbo.

The air is pushed back through the compressor housings on the turbo and it will either exit out of the air filter or pop off the stock intake tube from the turbo.

Ask any turbo rebuilder and they will tell you backpresure like this is unhealthy for your turbo.

Having an excess amount of oil in your intake system is NOT normal. This is a results of compressor surge pushing on the seals and oil leaking past them.

I am no expert, but the reason for a blow off valve is to prevent waves of air going back twards the compressor wheel. This tightens the nut on the shaft and will eventually break it in a gas car with no blow off valve. Surge can happen at to low of boost pressures as well. You see this alot with small honda engines using large shaft turbos like a Holset or similar. Low rpm surge is really not that bad though. Surge in the high rpm is bad news for your turbo. Its when the compressor wheel loses traction in the air and stalls. That is why it makes a woosh woosh noise, as the wheel slows it regains traction and starts to build pressue until it overspeeds again. Atleast thats how I got it explained to me.

 

[speed185187]

Ditto, everybody has to STOP comparing our tdi's to gasers. Totally different design.

 

[speed185187]

Air traction???

 

[bmwvw]

Air traction???

Yeah I was putting it into laymens term. Compressors are more like the wings of an aircraft they can stall just like a wing. Look at it as traction was an example to explain it better.You got a better deff?? make sure you quote wikipedia when you cut copy paste.

 

[speed185187]

Compressor stall

From Wikipedia, the free encyclopedia

Axis-symmetric stall", is a complete breakdown in compression resulting in a violent expulsion of compressed air out the intake, due to the compressor's inability to maintain pressure. In an axis-symmetric stall, the compressor has reached the limit of its pressure rise capabilities: local airfoil stalls quickly propagate to the entire compressor. The result of this is, the loss of the compressor's capability to maintain a pressure ratio and the subsequent backflow of all the air from the high pressure section

 

[bmwvw]

From Wikipedia, the free encyclopedia

Axis-symmetric stall", is a complete breakdown in compression resulting in a violent expulsion of compressed air out the intake, due to the compressor's inability to maintain pressure. In an axis-symmetric stall, the compressor has reached the limit of its pressure rise capabilities: local airfoil stalls quickly propagate to the entire compressor. The result of this is, the loss of the compressor's capability to maintain a pressure ratio and the subsequent backflow of all the air from the high pressure section

Yeah Losts of big words, but I pretty much said the same thing.

 

[bmwvw]

Look I was just trying to describe it in a way that evryone with out a physics degree would understand. Ok? sorry if I came off the wrong way.

 

[speed185187]

No need to appoligize, I just thought it was funny. Friends?

 

[OldSchoolFresh]

One of my hoses from the intercooler before the intake manifold got a tear in it so when my friend wanted to see how much air was coming it he put his finger on the leak, I revved it up, he let go and it sounded like a BOV, pretty cool. But I patched it with electrical tape, until I can get another hose.

 

[grtn316]

And with no throttle plate in a Diesel, where is this pressure build-up happening?

I have no idea...I keep asking myself the same question. I guess you could call BS on me claiming there is compressor surge but then I'd need an explination as to why my Intake keeps popping off of the compressor side of the turbo after letting off the pedal @ WOT. If this was a gasoline engine with a throttle plate, I would know the answer...



I have noticed that the EGR has a plate. Under what conditions does this plate open and close? Could it be closing when I let off the pedal. Perhaps its sorta stuck and its only partially open causing a restriction...


I really wish I knew the answer to this problem.

 

[grtn316]

From Wikipedia, the free encyclopedia

Axis-symmetric stall", is a complete breakdown in compression resulting in a violent expulsion of compressed air out the intake, due to the compressor's inability to maintain pressure. In an axis-symmetric stall, the compressor has reached the limit of its pressure rise capabilities: local airfoil stalls quickly propagate to the entire compressor. The result of this is, the loss of the compressor's capability to maintain a pressure ratio and the subsequent backflow of all the air from the high pressure section

If this was occcuring under WOT then it would be valid however, this is happing when I'm letting off of the throttle. So, "the loss of the compressor's capability to maintain a pressure ratio" occurs when I let off the pedal. Gasonline engines use a BOV to vent off this excess pressure to prevent damage to the turbo. This pressure exists due to the throttle plate closing.

In our paticular (diesel) case, there is no throttle plate so the air should continue to flow smoothly out the engine.

So the big question is, why does this exist in my car (if not all of our cars).

 

[speed185187]

Have you upgraded to T clamps for the rubber lines? They hold alot better than stock and don't change clamping force with temp changes.

 

[grtn316]

Have you upgraded to T clamps for the rubber lines? They hold alot better than stock and don't change clamping force with temp changes.

T-Bolts with prevent the pipe from popping off but it does not fix the damage that pressure is doing to my turbo. The intake side of the turbo is NOT supposed to see boost pressure.