EMP as related to the VNT 17/22

[buckweat diesel]

This isn't a I'm better than you thing. Its a, "why the hell was this machined this way?" thing. If you guys don't like how I think turbo shafts and wheels should sit concentric in their housings thats fine.
Why do you guys keep thinking I have problems installing these things? I don't, if I did I probably would have never measured anything or have said anything either.

ya know its like this
i bet u i build a motor diffrent then you right?
its the same deal with turbos its no diffrent!
we all do things diffrent even the factory thats why we tinker with this stuff right?

 

[Scott_DeWitt]

Why do you guys keep thinking I have problems installing these things? I don't, if I did I probably would have never measured anything or have said anything either.

How can an install ruin a turbo? Only things I can think of are leaving a screwdriver in the compressor, forgetting to install the oil feed line, or install a plugged/defective feed line, or dropping it?

Street Toys-- Regarding my post #35 I apologize I didn't mean to sound as if I was trashing you, I was discussing dabears post (#33).

 

[Passenger Performance]

ya know its like this
i bet u i build a motor diffrent then you right?
its the same deal with turbos its no diffrent!
we all do things diffrent even the factory thats why we tinker with this stuff right?

I'm all for doing things different, but I fail to see how a eccentric turbo is beneficial, just like I don't see how when building an engines you would benefit pistons/rods/cranks etc that aren't to the same spec.
If thats what people are happy with thats fine I guess. I suppose I am just a different kind of guy.

 

[Passenger Performance]

How can an install ruin a turbo? Only things I can think of are leaving a screwdriver in the compressor, forgetting to install the oil feed line, or install a plugged/defective feed line, or dropping it?

Street Toys-- Regarding my post #35 I apologize I didn't mean to sound as if I was trashing you, I was discussing dabears post (#33).

Scott you are right, its pretty difficult to screw up the turbo during install if you are paying any sort of attention. Its not difficult at all.

 

[nicklockard]

come to my class in january and ill tell u

I look forward to it. Call me some time. Need to figure out our parts/labor swap

 

[mrchill]

Anyways, sorry for derailing the thread.
EMP's are the effect of too much flow for a given volume, the volume is the constant and the flow is the variable. Now because these turbo's have variable vanes you can actually change the volume, and flow rate that makes it to the turbine wheel. Where the problem lies with these turbos is that even with the vanes wide open the volume is still to small to support the flow rate of the exhaust. So the volume maxes out but the flow rate keeps increasing and thus the pressure increases as a natural side affect.

Ah. How refreshing. A lucid and piognant answer to a question.......and on topic!

 

[Sootman]

Dave,
Thanks for the information (EMP's/EGT's).

 

[bmwvw]

Yes, this was a very interesting topic which I had little knowledge before. Thats why I like this site because of its seemingly boundless volumes of knowledge and insight. The post about vendors keeping a professional attitude on this site is very good advise. I recently bought pp520's from kermi and am very happy with the results. I may be in the market for a 17, but reading this post makes me a little weary. I may be a nub to posting on this site but I am also a paying customer and I hope you guys can find some common ground and sort your diffrences.

 

[nicklockard]

Yes, this was a very interesting topic which I had little knowledge before. Thats why I like this site because of its seemingly boundless volumes of knowledge and insight. The post about vendors keeping a professional attitude on this site is very good advise. I recently bought pp520's from kermi and am very happy with the results. I may be in the market for a 17, but reading this post makes me a little weary. I may be a nub to posting on this site but I am also a paying customer and I hope you guys can find some common ground and sort your diffrences.

Whoah there. You don't know the tenth of it. There are some super-sized McEgo's here that like to throw crap around. Don't rush to judgement...stick around a year and you'll get to know the cool people and the smack talkers.

 

[bmwvw]

Whoah there. You don't know the tenth of it. There are some super-sized McEgo's here that like to throw crap around. Don't rush to judgement...stick around a year and you'll get to know the cool people and the smack talkers.

I wasn't trying to step on anyones toes. Just saying It makes for a bad first impression on someone whos in the market for their services. Ya know what I mean

 

[LNXGUY]

I wasn't trying to step on anyones toes. Just saying It makes for a bad first impression on someone whos in the market for their services. Ya know what I mean

You are on the ball my friend I think the problem is people get way to uptight over some constructive critisism. I really don't think what Dave posted was a slam at all. He mearly took pics and measurements of what he found on the turbo he was about to install.. How did this get pointed around towards him?

Vendors need to grow some stones and own up to the fact that some of their product are faulty. Instead he blames the installer and insinuates that he messed up the turbo on purpose before the install in order to slam the vendor? Enough with the schoolyard antics, own up to your mistakes and make it right. This could have been solved in about 5 mins.

PP: "I noticed this turbo was out of wack yada yada yada, here are some pics and some measurements"

Vendor: "Really? Crap man, thanks for not putting it on the customers car, I'll send out a replacement asap, send me back the faulty unit and let me take a look at it"

PP:" Awesome, thanks.. OUR customer is happy it's being taken care of"

The end.

 

[jackbombay]

PP: "I noticed this turbo was out of wack yada yada yada, here are some pics and some measurements"

Vendor: "Really? Crap man, thanks for not putting it on the customers car, I'll send out a replacement asap, send me back the faulty unit and let me take a look at it"

PP:" Awesome, thanks.. OUR customer is happy it's being taken care of"

The end.

If I pulled a part out of a box and saw something wasn't right with it I certainly wouldn't install it especially when we're talking about a part that has a good possibility of taking out the whole engine (hydrolock/runaway) if it does fail before it gets replaced.

I think its pretty obvious what PPs motives were with the install and his posts here...

 

[Rub87]

Measured my emp with the vnt20..

Boost is greater than egt from 1900 till 3600rpm..

At 4000rpm emp is around 2.1 bar, it peaks at 2.3bar at 4200 and then it falls again..

When flooring in 5th at low rpm it surges at 1700rpm, then emp is around 1.6-1.7 bar and boost around 1.5bar..

 

[Passenger Performance]

You are on the ball my friend I think the problem is people get way to uptight over some constructive critisism. I really don't think what Dave posted was a slam at all. He mearly took pics and measurements of what he found on the turbo he was about to install.. How did this get pointed around towards him?

Vendors need to grow some stones and own up to the fact that some of their product are faulty. Instead he blames the installer and insinuates that he messed up the turbo on purpose before the install in order to slam the vendor? Enough with the schoolyard antics, own up to your mistakes and make it right. This could have been solved in about 5 mins.

PP: "I noticed this turbo was out of wack yada yada yada, here are some pics and some measurements"

Vendor: "Really? Crap man, thanks for not putting it on the customers car, I'll send out a replacement asap, send me back the faulty unit and let me take a look at it"

PP:" Awesome, thanks.. OUR customer is happy it's being taken care of"

The end.

YES! Finally somebody gets it.
Theres no need to take this stuff so personally, good grief its just a mistake and we are all human.

 

[jackbombay]

YES! Finally somebody gets it.

It's to bad you don't as you didn't iniate step #1 "PP: "I noticed this turbo was out of wack yada yada yada, here are some pics and some measurements" So it was impossible for Kerma to resolve the issue as he had no idea there was one.

This "got turned around towards PP" as this thread has nothing to do with the quality control of various turbos. Its about various turbo and how the resulting EMP one will/might expect to have from using them.

 

[Fix_Until_Broke]

EDIT: The gauges used to get the EMP data in this post are not accurate! I leave this post here for reference only. See below for measurements taken with an accurate pressure gauge.

Well - don't mean to take away from the "entertainment", but I have something on topic to discuss in this thread - sorry.

I got off my lazy bum today and put an EMP gauge in on my 17/22. I used the EGR port on the manifold, ran ~18" of stainless tubing up to ~ the MAF sensor then went to polyethelyne tubing through the firewall and mounted a 3rd gauge on top of my steering column dual gauge pod - kind of a pyramid and held on with duct tape . All tubing is 1/4" OD.

1st round of testing was using a 100 psi gauge, undamped, non liquid filled. I got ~20 ft down the road before I figured out this needs some damping - guage was un readable the needle moved so fast. Took one of the brass barbed adapters, soldered the end shut and drilled it out with a ~0.025" drill bit. Went for a drive and it was much better, still buzzed a bit when you really got on the throttle, but was readable at least. So now that I've bored you with meaningless details of taking the measurements, how about some results....

EMP:IMP = ~1:1 steady state. ~25 PSI Intake = ~25 PSI Exhaust at 100% throttle all the way through the RPM range. Exhaust would spike to ~35 PSI then settle back down to ~25 PSI. Part throttle is about the same, but EMP's go to 20-25 PSI even for ~5-7 PSI Intake then settle right back down to similar/same as Intake.

So seeing that the EMP's are relatively low, the 100 psi gauge has a lot of wasted space on it. I found a 60 psi gauge and plumbed that in - got ~same results. At this point I switched the gauges from intake to exhaust and vice versa. I was gentle on it the first few times, not wanting to overrange my boost gauge (30 PSI Stewart Warner). After getting a feel for it, I went out and did a 3rd gear run from ~1600 to ~4500 RPM at 100% throttle. EMP's never exceeded 30 PSI even on the initial spike and settled in 26-27 psi. IMP's read ~25-27 PSI on the other gauge (harder to tell since it was buzzing). I'll see if I can find a 0-40 psi gauge of decent quality to install (the ones I used were $6 and $8 respectively). Even though the gauges were cheap, swapping between IMP and EMP gauges as well as using three different EMP gauges shows that they're all similar at least.

All guages are bourdon tube style with 270 degree sweeps.

So from an EMP:IMP ratio the 17/22 hybrid seems to perform remarkably well.

Anyone in the Milwaukee Metro area who has a boost gauge and an EGR delete on a VNT-15 or VNT-17 or anything else with a stock EGR port? It's a pretty quick installation (15 minutes) if you've already got an EGR delete. I'd like to see what some other setups perform like.

Now back to the off topic discussion

EDIT: The gauges used to get the EMP data in this post are not accurate! I leave this post here for reference only. See below for measurements taken with an accurate pressure gauge.

 

[Slave2school]

That is good news! I wonder what someone with less of an open exhaust system will get I would volunteer but I woud need a TDI and turbo to go with it as the Ford doesn't have either

 

[jackbombay]

...TDIClub folklore was wrong...

I really didn't expect that but then again TDIClub folklore is usually wrong, bigger IC do nothing, Bigger exhaust does nothing, etc...

Thanks for getting that done.

Want to lend me you block of plate set-up? I'll pay shipping, we can see how a stock VNT 17 compares.

 

[Rub87]

I used very short steel brake line, like 4" or something..don't see why everyone is using such long tubes to feed emp gauge.. didn't have any troubles reading, needle was nice stable..

 

[bmwvw]

I got pp520's with a vnt-15 with an extra gauge if anyone wants to see some results from this setup i would be glad to install the gauge and see what i get. got some time on my hands and no money to buy anything cool right now

 

[KROUT]

Gee how will they bash this turbo now. Looks like the emp thing was more bs.

 

[IndigoBlueWagon]

Interesting data, Matt. Thanks for doing the testing. I wonder how this compares to stock?

 

[LNXGUY]

I don't think you need to worry about EMP's until you are getting close to the 30psi range or higher...

But it's always a good thing to keep your eye on.

 

[mrchill]

Thanks for the unbiased work Fixuntilbroke. I will try this on mine to see if I get similar, higher, or lower ratios. I have a hunch they will be a bit higher (EMP) as I am consuming a bit of oil. Will fix that soon. So little time.......

 

[KROUT]

I am going to try to rig one up to test on my car sooner or later.

 

[jackbombay]

Looks like the emp thing was more bs.

15's and 17's have been "known" here at TDIclub to be responsible for high EMPs, but it turns out it wasn't true . Remember when most everyone here was sure big exhaust did nothing for TSI performance? And big intercooler were pointless? I do, I knew those claims were BS, but I did fall for the high EMP/15/17 folklore, but th emyth has been busted and we can all sleep easier now.

But as usuall you are throwing stones trying to start fights.

 

[IndigoBlueWagon]

So help me out here. What if the EMPs were high? What's the implication?

 

[LNXGUY]

Exhaust gasses getting pushed back into the combustion chamber, high EGT's, etc.

 

[KROUT]

15's and 17's have been "known" here at TDIclub to be responsible for high EMPs, but it turns out it wasn't true . Remember when most everyone here was sure big exhaust did nothing for TSI performance? And big intercooler were pointless? I do, I knew those claims were BS, but I did fall for the high EMP/15/17 folklore, but th emyth has been busted and we can all sleep easier now.

But as usuall you are throwing stones trying to start fights.

Please define throwing stones Jack. A just who were these imaginary stones in head thrown at. If you take that coment as I am throwing stones then so be it. Exactly how does my statement show that I am trying to start anything. Please get technical on me and explain it.

 

[Fix_Until_Broke]

So help me out here. What if the EMPs were high? What's the implication?

High EMP's are like a restrictive exhaust (well, they actually are a restricted exhaust). If it takes 50 psi in the exhaust to drive 25 psi in the intake and you lower that to 40 psi exhaust and maintain 25 psi intake (via different turbo or exhaust or vane positioning), it's kind of (stress on kind of) like gaining 10 psi of boost pressure. Since the pistons on the power stroke don't have to work as hard to push the other pistons on the exhaust stroke, it frees up power without adding any more fuel.

A couple things have me thinking now...and in keeping true to my screen name...what happens if we lower exhaust pressures even lower, lets say 0.8:1 for example or 0.5:1?? What happens if we keep going lower? What's the limt?

The other thing (and I'm really not trying to start something here) is what was Street Toys testing where he saw these pressures?

If you want to monitor the real pressure on a stock 15 or a 17 or 17hybrid then I would suggest that you get a guage that reads 80lbs ! I think that you will really be amazed at the results!

This is why I started out with a 100 psi gauge - Hey, you cost me an extra $8 darnit. Just kidding, just kidding. Seriously, what turbo's were you getting 80 psi on the exhaust?