Max boost map gtb2260vk

[mk1-83]

Im working on my lupo boost map.
Im whant to know what the max boost of gtb2260vk turbo safe can do.

lets say about this map:

RPM - Boost bar
2000- 1.6
2250- 1.9
2500- 2.2
2750- 2.3
3000- 2.6
3250- 2.6
3500- 2.6
3750- 2.6
4000- 2.5
4250- 2.4
4500- 2.3
4750- 2.2
5000- 2.1

Can make the turbo safe this boost map ?

please add youre comments

 

[TDIMeister]

You need a compressor map for that turbo and plot something like the below, obtaining points from a engine calculator like from http://bit.ly/QBAWh7

Then you will know exactly when you're operating within the limits of the turbocharger for each RPM the engine is operating.

 

[Alcaid]

Would be really nice if that comp map was actually available to the public.

A turbo RPM meter would actually be very useful since exducer size is known it's just a matter of keeping the tip speed below 540-560 m/s and all good.

Measuring EMP vs. boost is also useful to see that turbine is not choking and that EMP:boost ratio is at a sane level to avoid turbo failure.

 

[TDIMeister]

A turbo RPM meter would actually be very useful since exducer size is known it's just a matter of keeping the tip speed below 540-560 m/s and all good.

Unfortunately this alone, as the above graphic illustrates, will not tell you if you're operating in surge at low RPM or choke at high.

Measuring EMP vs. boost is also useful to see that turbine is not choking and that EMP:boost ratio is at a sane level to avoid turbo failure.

It's a good approach, but you really need a map and do some math. If you don't have the exact map, one with the same exducer diameter and trim from the same manufacturer will suffice as a reasonable approximation. There will be a lot more error in the calculations for the estimates of BSFC and VE anyway...

 

[Alcaid]

Unfortunately this alone, as the above graphic illustrates, will not tell you if you're operating in surge at low RPM or choke at high.

Surge you'll hear or even see on the boost gauge if it's really bad And wouldn't you see compressor choke on the emp gauge as drive pressure will increase rapidly due to the stalling compressor?

I plot these RPM lines with varying VE, BSFC and IAT for each line and I agree there are lots of variables to mess up the output but at least a map from the same family compressor would tell a lot about at what PR compressor efficiency islands are at and what and where max PR is available. Predicting the map change for a change in trim is not very difficult if one has seen several maps within same compressor wheel family before but then what would be a map of a "brother" of the mentioned 60mm 55trim comp wheel?

I know this data is not to be shared by those who have access to it so I guess we'll never know.

 

[TDIMeister]

Surge you'll hear or even see on the boost gauge if it's really bad And wouldn't you see compressor choke on the emp gauge as drive pressure will increase rapidly due to the stalling compressor?

On the former, yes, but that's not how I do engineering. On the latter (apart from the misnomer of calling a choked compressor as stalling), not necessarily, because the definition of choke is that PR (and shaft RPM) are increasing rapidly without an appreciably correspondent increase in mass flow. Since we're talking about a ratio here, two numbers that make up the ratio both increasing simultaneously will not tell you much. An increase in the EMP:MAP ratio will, however, tell you that total turbocharger efficiency is getting worse and at least that the turbine is becoming the greater bottleneck than the compressor.

I plot these RPM lines with varying VE, BSFC and IAT for each line and I agree there are lots of variables to mess up the output but at least a map from the same family compressor would tell a lot about at what PR compressor efficiency islands are at and what and where max PR is available. Predicting the map change for a change in trim is not very difficult if one has seen several maps within same compressor wheel family before but then what would be a map of a "brother" of the mentioned 60mm 55trim comp wheel?
I know this data is not to be shared by those who have access to it so I guess we'll never know.

These could be close.

 

[Alcaid]

Let's not hope it is anything near the first map, peak compressor efficiency of 71% and Garrett didn't bother dyno (or plot) the map for anything more than a tip speed of 484m/s

The lower one looks more up to date but again no speed lines for anything over 482m/s, one can guesstimate where the next speed lines will go though and I guess all forum members here with a GTB2260VK run them with more PR than what is within these maps.

The Holset HE221W map would propably be more useful but Garrett will not be anywhere near the map width that turbo has, so keep a good distance from the surge line I'm guessing the max flow also is less on the GTB2260VK even though it has a slightly bigger inducer diameter

 

[TDIMeister]

Garrett probably plotted the maps conservatively knowing that amateur enthusiasts will push them beyond the published specs anyway and didn't want a large amount of warranty cases of units being pushed to their bleeding edge limits. Also, the larger GT28 frame size turbines cannot spin as fast anyway.

Keep in mind also that the above turbos are using first generation GT aerodynamic technology, so tip-speeds and peak PR are more constrained, efficiencies generally lower and same for mass flows at a given RPM. That's why I'd always rather have the latest generation turbo.

 

[mk1-83]

Can I safe run this map I made ? Any one run the same map..

 

[Alcaid]

That exact same GT28 turbine is spun 30.000rpm more on the GTX2860 turbos. One of the facts they tend to forget to mention when they market the wonderful high PR ratio the GTX turbos can deliver compared to the older GT of same size. On some of the GT vs. GTX comparisons they also forget to mention that wheel dimensions are slighly bigger and no wonder why it flow more air then. Garrett knows marketing, let's give them that

 

[loudspl]

Can I safe run this map I made ? Any one run the same map..

2.6 bar is good/safe. 2.8 bar or more really no difference IMO.

Need more flow.. 2260 only good for max ~35lbs/min

 

[storx]

Im not sure if RyanP has different opinion since more cars are running the 2260, but when i was setting mine up, he said to not go above 2.7bar

 

[mk1-83]

Thanks can it do 2.6 @ 3750 rpm ? Its also at what rpm the boost is.

 

[loudspl]

Im not sure if RyanP has different opinion since more cars are running the 2260, but when i was setting mine up, he said to not go above 2.7bar

What I meant is there is little, if anything, to be gained at above 40psi on this turbo. I did not see a difference in 2.6 bar and an older tune @ 2.8 bar. I'm guessing we are already well outside the efficiency map for this GTB

Thanks can it do 2.6 @ 3750 rpm ? Its also at what rpm the boost is.

How closely does specified follow actual in previous maps? Need to make sure there was no overboosting (good actuator, vanes not sticking).
You can try that map, do a log group 011 and see if actual is higher. If so, I would request less. These GTBs are tough but there is little to no benefit in requesting more than that IMO

 

[storx]

Thanks can it do 2.6 @ 3750 rpm ? Its also at what rpm the boost is.

Yes, when I get home I'll post my boost graph from my setup for you

Sent from my SGH-M919 using Tapatalk

 

[mk1-83]

Thanks.. Now got bigger problem.. Yesterday the 4* gear whent out. It happens when i pull up on the highway i slowy go on the gas them suddly it popt. I got home luckly
How much torq can hold a 02a gearbox ?

 

[Digital Corpus]

I've run 300-325 through mine without any problems. It's probably a little higher than that now.

 

[mk1-83]

Im running around 500-550 nm

 

[sali87]

we had an ibiza with 500nm and 02j

 

[mk1-83]

Ok so 500 nm on a 02j box. The 02j have same internals as a 02a box. I think to limit torq low down to450-480 nm

 

[Digital Corpus]

Adding to the pool of info:
http://forums.tdiclub.com/showpost.php?p=4454009&postcount=366