Can't keep 210kpa boost pressure 5000RPM

[biondi]

I'm now calibrating my G2X (export variant of Saturn Sky Redline, A/T) with 3bar Map sensors.
With stock K04 turbo, I couldn't keep 210kpa(=30.45psi) boost pressure over 5000RPM and dropped to 170kpa at 5500RPM, 160kpa at 6000RPM.
And I thought that's the stock turbo's limitation.

So, I bought a modified K04 turbo from ebay.

http://www.ebay.com/itm/282031572687...%3AMEBIDX%3AIT


After installing it I tried to check boost pressure.
But I couldn't get any significant change...
So, edited DAL table and checked several factors but it's almost same...


Can anyone check my tune and log files?
I wonder I missed something or the turbo is not enough to provide 210kpa over 5000RPM.
My purpose is keeping 210kpa from 4000RPM to 6300RPM at WOT.

Before buying this turbo, I told my purpose to the seller and he said it would be enough.
So, I installed it very quickly as soon as I receive it....


Thank you.



2008 G2X 5GDMF35X28Y120696.hpt
16-05-12 02-20-48.hpl
G2X layout.Layout.xml

[JimmyS]

In your tune file go to Torque Management>SC/TC Boost Control>Pressure RPM Factor and raise 3000 to 6000 settings from 3.101 to 3.500 and see how it responds. You may need to raise it a bit more or lower it from there but it should get your boost up.

When you're calculating your boost pressure, you have to subtract your atmospheric pressure so your 30psi is really 16 give or take depending on your atmospheric pressure.

Your purpose should also include getting the rest of the tune in check before getting carried away with a lot of boost. Your PE table for example is really rich above 4k in the 100% column and the remaining 3 columns shouldn't be set at 1.00 across the board. Timing is low, WG duty is high, etc..... You have the tools to make some decent power but don't assume that you can just throw a bunch of boost in without addressing the entire tune.

EDIT: Your log shows that your boost low res is 267 (roughly 24psi) at 5860rpm with 6*KR. Time is 11:14:15 to 11:14:18. Again at 11:15:33 you are at 280kpa with a bunch of KR. You really need to work on the rest of the tune first before you blow something up.

[cobaltssoverbooster]

First off you don't read map sensor for boost. You need to read the boost lo res sensor for adjusting boost.
Second if your reading it in kpa you need to subtract 101 from the sensors actual kpa reading.
From what Jimmy says you have maxed the factory housings out pressure wise. If you want to boost over 24 psi on a stock turbo then expect to pay the hefty rebuild cost for a engine and turbo.
Third your kr is high. If it was .5 to 1 I probably wouldn't say anything but at 6 the engine isn't happy. Lower your boost and work out your fueling and ignition. Then once you got those methods down pat creep the pressure up to your desired goal.
I've destroyed many vehicles running 24 psi on bad tunes with my 22 psi cobalt on a fantastic tune. No need to get hasty on boost pressure with the stock turbo. It can't take what your expecting from it and it's going to take a bunch of other stuff with it when it goes.

[biondi]

In your tune file go to Torque Management>SC/TC Boost Control>Pressure RPM Factor and raise 3000 to 6000 settings from 3.101 to 3.500 and see how it responds. You may need to raise it a bit more or lower it from there but it should get your boost up.

When you're calculating your boost pressure, you have to subtract your atmospheric pressure so your 30psi is really 16 give or take depending on your atmospheric pressure.

Your purpose should also include getting the rest of the tune in check before getting carried away with a lot of boost. Your PE table for example is really rich above 4k in the 100% column and the remaining 3 columns shouldn't be set at 1.00 across the board. Timing is low, WG duty is high, etc..... You have the tools to make some decent power but don't assume that you can just throw a bunch of boost in without addressing the entire tune.

EDIT: Your log shows that your boost low res is 267 (roughly 24psi) at 5860rpm with 6*KR. Time is 11:14:15 to 11:14:18. Again at 11:15:33 you are at 280kpa with a bunch of KR. You really need to work on the rest of the tune first before you blow something up.

Thank you for your advice, I needed it such as your answer.
And I'm reading the boost as [Boost LowRes] - [Baro], of course.

There are some questions...

1. Regarding AFR in PE table, I would make it 12:1 above 4K and full boost. If it is rich, what AFR should I make?
(I've learned 12:1 is the best AFR for power, and 14.7:1 is ideal AFR for fuel economy at high school, about 20 years ago)

2. You said 'timing is low', what is the 'timing'? and what is proper WG duty?

3. Regarding KR, it seems that the fuel quality is very low... I will adjust KR with premium gasoline again.


I need to study harder ^^.

And I would like to show you a video.

http://tvpot.daum.net/v/v1d6fbcewbnVoHotbxtUeto

Of course the turbo is not stock. It is EFR6758 or something.
My last goal is making my car as the video.

[TurboCobalt]

I can't open your files since i dont have 3.0 yet, but i'll try to answer your questions.

1) Port fuel injection needs a richer mixture to cool the combustion chambers. Direct injection has a cooling effect on combustion chamber therefore it can run slightly leaner. I believe most people run 0.86 (maybe as high as 0.88) lambda for best torque on this forum.

2) when people talk about "timing" they are talking about spark ignition with respect to crankshaft angle. so timing of 12 degrees is a spark ignition of 12 degrees before Top Dead Center on the piston. positive values are spark advance, negative values are spark retard.
for WasteGate duty cycle i would run the stock table until you figure out knock. you can get pretty high boost pressure without messing with that table. I only changed it very slightly and only at high RPM.

3) you should only run premium fuels in these engines, especially if you are trying to tune it. Basically run the highest octane fuel you can get from pump.

[JimmyS]

Definitely run the best fuel you have available.

Start studying by reading the LNF threads and watching the videos at the bottom of cobaltssoverboosters post and when you have read and watched them a few times and have a good understanding of them, read them again before making changes. There's lots of good information there. I would suggest you load your stock tune for now.

Another thing to keep in mind is that you can also tune the transmission but I wouldn't worry about it for now though it is the only way to increase your rev limits with the auto trans.

[cobaltssoverbooster]

Thank you for your advice, I needed it such as your answer.
And I'm reading the boost as [Boost LowRes] - [Baro], of course.

There are some questions...

1. Regarding AFR in PE table, I would make it 12:1 above 4K and full boost. If it is rich, what AFR should I make?
(I've learned 12:1 is the best AFR for power, and 14.7:1 is ideal AFR for fuel economy at high school, about 20 years ago)

2. You said 'timing is low', what is the 'timing'? and what is proper WG duty?

3. Regarding KR, it seems that the fuel quality is very low... I will adjust KR with premium gasoline again.


I need to study harder ^^.

And I would like to show you a video.

http://tvpot.daum.net/v/v1d6fbcewbnVoHotbxtUeto

Of course the turbo is not stock. It is EFR6758 or something.
My last goal is making my car as the video.

this is not true for your model of engine. 12.6-13 afr under boost. also the boost lo res has a hard offset of 101 which is why i mentioned subtracting 101 kpa.
timing under boost for kappa platforms on pump gas starts around 13-14 * all in and if its a cobalt/hhr platform then you can run 14-15* all in as a start.
ignition that's too low cause kr, ignition that's too high causes kr, and too boot the ecu model in question here is highly sensitive to ignition advance values and fuel mapping so when they are off it throws a kr fit like you wouldn't believe.

[biondi]

Yes, I have already read entire LNF threads and saw the videos a dozen times.
And now I'm trying tunes on my car...

But.... I should read it several times more.

Thank you.