Diverter Valve - Do I need one

[mikepologti]

on a stock turbo it might make a bit of noise but on a chipped polo it makes a lil more (higher boost pressure ) . as far as a stock car is with a stock diverter valve , its fine. the germans make there cars pretty good from factory when factory tuned and only tend to go a bit out the window if people either a/ thrash the living daylights out of them or b/ tune them. hope this helps. also its also worth noting make sure you get a semi atmospheric bov as the fully atmospheric will send you into limp mode. as for the noise , its noticable but if your after a scooby or a skyline "woosh" then to take a line out of the movie "the castle" ...."tell him hes dreamin"

[noone]

Agree with Mike.

You can get a noise from the Forge / Ebay style ones, but not the same as the ricer BOV.

The upgrade is to work with higher boost levels, so not really usefull on a stock car.

[fuzion]

i would grab a Bailey, GFB or Forge followed by APR's .. They would be my order and from experience i would myself personally stick to a bailey and gfb from using about 7 different ones testing/dyno'ing etc.

The oem ones will eventually leak and also not hold the boost properly as mentioned.

[hotcar1600]

Hey Guys,

Thought I would provide an update if anyone is interested!!

I have had the chip in for about two weeks now and I must say the improvement has been vast!! The extra power is what this car should have been like standard. Now I want more power. One thing I definately have noticed is that the power of the car does vary much more in hot weather etc, much more noticable than before, nonetheless Im not complaining!!

In terms of diverter valve, the shop that installed the chip said mine wasn't faulty and they either work or they done. Im not convinved though, I think the boost does fluctuate a little and it does have a noticable surge when coming on and off the throttle violently!! i think that will be my next modification!!

I also got the engine mount done but I must say that I still am having gearbox probelms when shifting into third! I did chenge the oil over but when I suggerested an organince oil I recieved a dumbfounded look by the shop. Im thinking I will just buy the oil and give it a try myself as Jmac has suggested. I will search the forums and see where and how to do this myself.

All in all though I am quite happy with how smooth the power is!! I want more now though .

Thought I might add that I also installed a BMC filter and Seat Intake hose - the difference I find is that it brethes and pulls slightly harder in the top end with an ever so slightly reduced amount of torque down low. Bang for your buck though it makes the chip look invincible!!

Cheers

[noone]

In terms of diverter valve, the shop that installed the chip said mine wasn't faulty and they either work or they done. Im not convinved though, I think the boost does fluctuate a little and it does have a noticable surge when coming on and off the throttle violently!! i think that will be my next modification!!

I also got the engine mount done but I must say that I still am having gearbox probelms when shifting into third! I did chenge the oil over but when I suggerested an organince oil I recieved a dumbfounded look by the shop. Im thinking I will just buy the oil and give it a try myself as Jmac has suggested. I will search the forums and see where and how to do this myself.

Hey mate, good to see you are enjoying the car.

The diverter valve isn't just about working or not working. There are 2 functions to the diverter: 1, when vacum is applied (managed by ECU) the Diverter bleeds off boost. This can be done to help keep the boost in the mapped sweet spot, but is regualted more by the N75 Valve. The second function is more relevant to an upgaded car: If enough pressure is applied to the diafram / mechanism, the valve opens, allowing pressurised air to be recirculated (mostly lost). The amount of boost the valve can hold is a function of its design. I don't think the stock ones can reliably hold 17 or more PSI, so it may have been bleeding off the spike of boost or maybe holding up fine for the time being.

You got the ebay one? Which spring are you using? if the tension / spring is set too hard, it can create a jerky response when coming off throttle.

More power is not the easiest thing to achieve after the Chip. There are little ways to gain a bit more, but TBH, it gets expensive for little gain.

The stock SMIC gets heatsoaked pretty easily. The FMIC (based on my fininds with the Forge unit and research) will not add much power, but will keep the power you have when the system is cool. When the turbo gets hot, the little SMIC can not keep up.

Which Chip? APR? If so, it might be worth resetting the tune with the new components so the enging can addapt to the new parts. Its not going to be night and day, but a good idea IMO.

In relation to the surge, the intake should help smooth this out, but this seems very dependant on the tune and car. Some people have found that by changing the N76 valve to a different version (eg N75-J) that the car boosts more smoothly, harder or other sublties. I found the FMIC made a difference as well, not sure why TBH.

Sucks about the gearbox, I'd go with the redline...

And as I keep preaching, Vag-com is your friend. You can see a lot of whats going on with your car when you log it, easy to see if its doing everything it should or may help point out a potential issue keeping you from making the most of your toy.

This picture may help a little:


Taken from this thread on Vortex: http://forums.vwvortex.com/zerothrea...111538&page=23

[jesum]

I had the surge too but I later found out it was because the local APR dealer had loaded the wrong map on my car. I could clearly hear the frequency hiss of the turbo changing like a sine wave. That particular dealer has since been terminated from the APR network.

The *other* APR dealer was the one who identified the issue and corrected it with the right map. The boost is now smooth as a baby's bottom.