Upsolute Stage II, PP520s, 24 PSI Spike!?!

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Veteran Member
Joined
May 14, 2005
Location
AZ
TDI
2003 Golf
I watched in horror as my boost guage reported a 24 P.S.I. spike while I was rolling on the power in second gear this morning. Level ground around sea level, engine fully warmed, air temps in the low 40s. I have the stock turbo and am running Upsolute Stage II software with PowerPlus 520s. I've been driving with this setup for over 10,000 miles now and haven't seen it go above 20 (usually around 18-19 PSI.) Was this a fluke, or a sign of bad things to come?

Thanks
 

Eck

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Sep 21, 2003
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was: CA, 95630 now: Bavaria 91058
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Golf TDI 2003 reflex silver 2dr, 5 speed
If you're still running with the VNT 15, adjust the actuator rod longer by one turn. That'll do it. The boost valves is just another thing that can go wrong. There is no need for one. It seems like the cool thing to have but I never bothered.
My 15er ran 20psi sustained with 216 injectors for over 1 year. A good software and a little adjustment will do it.
 

Golf_GTDI

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Jun 12, 2004
Location
Logan Ohio, USA
TDI
2001 Golf GLS
Holy cow... the boostvalve is not optional in my mind. I also would not go messing with rod adjustments on the turbo.

The boostvalve is a high quality device that helps cure boost spikes by a very simple and reliable means and will help keep your car running well for years, not a year.

I know this means nothing seeingas its a small sample test but I had RC3 and PP520s done at the same time another friend had RC2 and Sprint520s done and one of us had to pop for a new turbo inside 6 month. It was NOT the guy who had the boostvalve nor was it the guy with the more aggressive tune. The things work.
 

20IndigoBlue02

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Aug 22, 2001
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Was North NJ, now SoCal
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2002 Golf TDI-- deceased
I agree.. messing with the VNT actuator rod.... well I personally cannot do it-- too much risk..especially if you adjusted it improperly.

A Boostvalve or Dawes Device is installed in parallel to the N75, so yes, it is a redundant boost controller, however, the thing does an excellent job of preventing the spikes.
 

KERMA

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Sep 23, 2001
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here
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99 beetle and 04 jetta
IF you log Upsolute boost in Vag-Com, you will see that the boost appears stock or near stock (unchanged from stock.)

Then compare what you see to your boost gage. They are very different. Boost gage reads higher than vag-com.

What this tells me: Upsolute doesn't change the boost map much if at all. Instead they change the data bit that relates the MAP sensor output to boost. IOW kind of like a "boost bleed" inside the ECU programming instead of a re-map.

This gets you more boost, but it is less damped (less controlled.) Spiking/undershoot is an unfortunate side-effect of this approach to programming. It is a well known and documented characteristic of Upsolute programming. It is why folks started using Dawes Devices to control the undershoot.
 

KERMA

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Sep 23, 2001
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here
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99 beetle and 04 jetta
You can also adjust your stop screw in a couple of turns to help the spiking. It will also slow the response, but that is what you want.
 

Jaco

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May 5, 2000
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Leuven (Belgium)
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Polo 1.4 TDi , 04 , black
sticking vanes maybe ?
The VNT mechanism doesn't open up fast enough , hence the spike ?

I have no personal experience with VNT turbo's, but this scenario has been documented here several times...
 

20IndigoBlue02

Top Post Dawg
Joined
Aug 22, 2001
Location
Was North NJ, now SoCal
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2002 Golf TDI-- deceased
KERMA said:
IF you log Upsolute boost in Vag-Com, you will see that the boost appears stock or near stock (unchanged from stock.)

Then compare what you see to your boost gage. They are very different. Boost gage reads higher than vag-com.

What this tells me: Upsolute doesn't change the boost map much if at all. Instead they change the data bit that relates the MAP sensor output to boost. IOW kind of like a "boost bleed" inside the ECU programming instead of a re-map.

This gets you more boost, but it is less damped (less controlled.) Spiking/undershoot is an unfortunate side-effect of this approach to programming. It is a well known and documented characteristic of Upsolute programming. It is why folks started using Dawes Devices to control the undershoot.
May be very well and true... however the stock ALH programming spikes as well as RC'd cars.

Didn't oldman mention something about the programming is on the threshold of the VNT-15 sweet spot and where is spikes a lot?
 

Eck

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This is a older VagCom boost readout of my then VNT 15 @ 20psi with rod adjustment. No secondary boost valve. It can easily be done if your chip guy considers the rod adjustment. It doesn't get nicer then this. I drove it like this for over 1 year w/o any hickups. This was also dynoed at 140whp and 250 ft.lbs. with Bosch 216 and TT pipe. Chip by Mozz/Austria, nothing else was done.


http://
 

KERMA

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The usual tradeoff is turbo response versus spiking.

It looks like there is some lag with that setup, along with overshoot in the lower gears. It's tough to find the right balance. What matters is that is works for you.
 
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