will have pics tonight

 

That's what I was getting at earlier, but you just said it better then me.

What I really want to see is the mating surfaces on the VW and Audi's and how they differ from on in the MINI turbo housing.

 

I figure they would be the same, i believe they use borg warner chargers as well. I will pull the sucker apart today when i get home and just insert the plunger to see how it fits. should be "a" ok.

 

Ok guys...


Bad news....


CZAR is right to a certain extent.

I am not gonna post pics because there is an easier way of verifying my findings. Mind you i have been studying this design for the past week.


The VAG will NOT hold a tight seal. the rubber diaphram(on the inside of the valve , the yellow piece) is integral to making a tight seal. the plunger is not the important part. No matter how tight the plunger on the vag is, if you blow on it just lung air pressure will escape as it is not INTERNALLY air tight. Air will escape between the plunger and the tapered seal of the plunger against the dv cap that holds everything together.


My recomendation is take it off! touche to CZAR for starting this investigation.

Im taking mine back tomorrow.


Like i said... pull it out and blow on the plunger itself and you will see that it leaks air.

Sorry guys. If you have questions ask.

The design of this valve im sure is for added drivability so the slight leak makes things smoother as the air is not bursting out.

 

Well now I am happy I got mine before the designe change. The one I have has the same designe as the stock mini DV only with larger holes.

 

So the VW and Audi guys are assed out too then? They do in fact have the same housing as expected. Very odd

 

Big, did you drive with it installed? Impressions?

 

Tested the differences. Definitely a difference in smoothness but i registered a whopping 1.2psi drop in 3 wot max boost. The loss i think will also be variable to the amount of boost being run, more pressure= more loss and vice versa.


It is not air tight unfortunately. Now like CZAR said before thought the amount of air lost is going to be minimal. I am on the go fast side of things so any air lost for me is too much for my personal mission.


Area in red is where air leaks from. Like i said the size of the holes don't matter as they are there to allow are to escape the internals. The internal sealing ring around the plunger is just not tight. I wonder if any vw audi guys have a remedy for this




Like i said before the design is good, i'm sure it would definitely smooth things out as the transfer of air is smooth instead of a burst.

Just because is not a tight seal does not mean its not a good mod. if smoothness is what your looking for then get it for sure.

VW and audi guys are loosing boost because of this, i even tried to use a similar like diaphram but it causes too much resistance as the cover for the innards has slim clearance.

 

Interesting, I too noticed that at crusing at 60 or so before VAG, pushing the throttle would net only about 15- 16 PSI and after VAG could only hit about 13.5-14 PSI. However spiritedly going thru gears before VAG would push 18 PSI max, but can get 20+ after VAG plus the shifts seemed much smoother. Maybe mine is broke . Thanks a ton for your input Big .
P.S. I blew on the stock valve installed on the VAG and it seemed airtite to me, did not try with VAG in stock housing. Might take things apart in a couple of days as it's snowing now . Gotta love Minnesota.

 

When you blow on the VAG youll know exactly what i mean

 

Damn you now I wana pull it off and mess with it. I'm getting an increase in peak boost and seemingly no power loss, but you have my curiosity going again. Why couldn't you post when I was back at the shop

 

I know what you mean. i was super excited not to have DV noise but now i figure because its not a rush of air. Tell me what you think. i think it can be remedied but its gonna take some tinkering.

 

The VAG hybrid doesn't have a rubber diaphragm.

Which is the impetus behind the VAG modification. A JCW turbocharger combined with an aggressive map will overtax the diaphragm from both increased heat generated by higher boost pressures, and rapid ballistic movements. Those who experience fluttering on throttle lift off are aware of how rapid diaphragm movement can be.

Mike, you've tested the realities of the pressure loss and its relative relation to boost produced and discovered it's not so bad, probably even beneficial to driveability. I would guess you are not producing stock boost levels and probably have your boost cut threshold raised as well. There's an appropriate application for the VAG modification, and there is an appropriate place for the spring alone. I would venture to guess the elaborate shape of the VAG escutcheon is an accommodation for the conductive and convective heat present so close to the turbo housing. I wouldn't feel any more fearful of the VAG plastic than the MINI plastic. The alternative to plastic is all metal like the Forge BPV, which BTW has been modified recently to allow more bleed-off/recirculation than previous versions, but it has its own maintenance issues. The VAG has been in high power MINIs for two years, and Audis producing more boost than the MINI turbo is capable of, it's not like it is untested for reliability.

 

I put the Audi piece on yesterday and haven't really had enough road time to fully assess the changes,but all seems positive.There is an increase in smoothness,feels like earlier(in the rev range) boost but a bit of a "lazy"feel at low revs at part-throttle when the engine is not up to operating temp.With higher engine temp all feels very good-better than before installation.Full throttle feels great,more than placebo.I used the WMW unit as the diverter valve core by the way.I realize there is likely leakage-but I won't take this thing off for love nor money!!
Happy.Wonder how long it will last.
Rod

 

No placebo here. highway speed (65mph) I am up 1.5-2psi over stocker. With this mod I can run Jan's High boost tune up to just under 20psi where I had problems with the stocker at about 18psi. I can now feel torque steer without the tune now that I did not have before.

I believe I am building boost quicker, the response is smoother and I am a happy camper. In my opinion this was one of the best bang for the buck mods I have done.

 

Highway speed? what do you mean by that like WOT at highway speed? I have the jan tune and have always been at 20-21 psi. WOT for me on the high boost tune is 18.7-19.xx. If you take the valve out and blow on it you'll know what was tested. It still has a great effect either way but the fact is you will be loosing pressure. How much? not a lost because only so much air can escape at a certain pressure but it is leaking.

 

Sorry guys for interrupting your thread, but it seems like a few facts have been omitted from the story, that could help you understand what goes on with the VAG bovs.

VAG bovs and our stock bovs are made by the same company, Pierburg.
They are installed on Borg-Warner KKK Turbos, on VAG and BMW/PSA turbo engines. Their piston's seat on the turbo is exactly the same, whether it be for a Golf V GTI or a Mini.

The first versions of the TFSI VAG bov closely resembled our stock bovs.
You can see the two bovs next to each other in the original article on the upgrade (sorry for the mess in the engine bay - it was from my wife's 207 CC many years ago).

http://www.etuners.gr/index.php?s=12&t=13


But because they had the same problems we do with valves tearing apart, they upgraded their bovs to the new design. And have been using that in the new TSI engines with excellent results.

The new design features a piston without a silicone diaphragm, which helps with reliability a lot. It does not get torn or broken any more.

Below you can find the new bov interchange guide, which was tested when it hit the market and being used ever since.

http://www.etuners.gr/en/index.php?s=12&t=2


From my experience, there have been very few cases of bovs resulting in boost related issues. All of them had to do with the assembly of the crown and the piston on the stock (BMW) bov body, but still they were very few in numbers.
Most of the problems came from bad fitting between the yellow O-ring and the plastic inner cover. Be careful when putting it together, you might need the VAG bov's O-ring instead of the stock one.

If you are still experiencing lower boost problems, you can use the full VAG bov body, but you will need to convert the stock electrical plug to VAG.

In the 4 years I have been doing this modification, I have only seen higher boost levels rather than lower using the VAG bov. It has also survived extended abuse in big turbo kits and hybrid turbo kits without problems.

And in Audis and VWs, it survives daily abuse at insane boost levels with extremely big turbo kits.

So why not use the manufacturers' upgrades?

 

I see your point. My initial concern was that if it does come apart, as the stock ring already does, there would be smaller pieces coming off rather then the typical big chunk. All in all I have been fine with how it works, I've put close to 3k on the car since I installed it. Just had my small worries you know.

 

Just found the 710D version on-line for $69. Gonna order in the next day to week and pop that puppy in, I see the pro-con battle going on but the way mine is acting I may have a semi-ruptured diaphragm already, seems the on-off boost is sometimes way more twitchy than it ought to be. I can live with possibly sacrificing a small amount of peak boost for improved over-all driveability, I'm looking more to destroy twisties than to 1/4 mile, and in the twisties smoothness is the winner of the day, you dont want heavy boost hitting in the midle of an off-camber descender. You and the guiderail may become instant good friends.

 

Unsure if this would be a good thing or wouldn't work at all. What would happen if we seal up the DV area with a block off plate and then proceed to use an external BOV ?

Would this work and would it be beneficial

 

I can't see that moving to an external BOV would hurt anything but would you really gain? Is there an external valve that functions so much better than the VAG that it would be worth all the extra engineering? Just curious.

 

What does this do?


http://www.forgemotorsport.com/conte...roduct=FMDVMCS

 

BOV relocation is very easy. Once you have blocked the stock bov port with a proper cap,
you install a conventional bov on an intercooler/boost pipe.

Then connect the boost port (Alta/ATP/BSH etc) to your new bov's boost command.

You just need to leave the stock bov connected so that the ECU will think it is still on.

 

Cruise control set at 65mph Highway speed. I have a 50mile one way commute daily so I can test things in a semi controlled environment. So same conditions, same speed MY boost is up 1.5-2psi over the stock dv.

 

At cruising speeds your in boost? I'm pretty much in vacuum at cruising speeds. I wonder what I am missing about this valve. It was not are tight so I need someone else to do the blow test So someone can see what I mean. Mike pull the sucker out it takes 10 min