Need some advice on too much low end boost after factory turbo replacement.

2 Attachment(s)

Hi all. As the title says I'm currently confused how to control the low end boost on this car after I replaced the turbo. The car has 280k on it and the turbo started showing definitive symptoms of the turbo failing. It had 3 cracks and the fins were scraping the tunnel pretty good. It was originally tuned by zzp and I started to branch off from there. I have a zzp catless downpipe with the highflow cat in the intermediate pipe and the zzp cold air intake. Other than that there are no other mods. Now that I replaced the turbo I'm constantly seeing 2-4 pounds of boost over desired on the low end. There was a lot of overboots thought the whole rpm area which I contribute to it being tuned with it performing poorly (turbo) at that time. I'm getting constant high levels of KR on the low end as well even sometimes at idle and I can only assume its from the overboost. That's my assumption since none of these things were occurring before the turbo was replaced. A bunch of misfires and KR has started after I replaced it. Could this mean the new turbo is bad and I'm way off on what is causing these issues? The waste gate DC table is at its minimum of 5% at 1.1. I've been slowly bringing the rest of the table back into sync with desired boost bc there was a lot of overboots thought the rpm range but I am getting a bunch of surging now that I'm guessing is from it still being out of whack. I can't really give this car any heavy amount of pedal before it starts pulling timing as well. It has made it interesting merging onto the highway. It feels like it has no real power at this point and is getting quite frustrating.
I've lowered the pressure delta factor table 1,000 rpm cell from 1.40 to 1.11 and can't really tell if that helped. I also changed the 990 lb/h cell in the turbo overspeed max pressure ratio from 4.50 to 4.30 still with no huge notice of change as well. I'll post my current tune file and my last scan. If anyone has any insight of what could be the culprit or anything I'm doing wrong or scanning wrong I would greatly appreciate it. I'm not sure how much more hair I have to pull out over this. lol

Attachment 125102
Attachment 125103

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Is it the same kind of turbocharger?

Here's what you do - undo everything you have done to the tune that ran just fine on the old turbo.

1. Check your wastegate actuator rod preload, should be about the same as the old one. Doesn't have to be that precise, but a good thing to check so it's not way off.

- Under airflow / turbocharger tab
3. Set your whole Base DC table to 0 and copy to Base DC Scav (my car doesn't use the Base DC Scav table at all so i just have it set at 0 all the time). Any value here below 0 or above 100 make no sense.
4. Make sure your underboost/overboost tables under diagnostics are not in your way.

5. Make a wide open throttle pull in a higher gear, 3rd for example, from very low RPM to the redline and log. You should see some amount of boost pressure - that's your wastegate spring boost pressure.

- Under airflow / turbocharger tab, again
6. Fill out the "Wastegate Open Boost" table at your barometric pressure (which i assume is 100 kPa unless you live on a mountain) to the measured wastegate spring boost pressure and guesstimate the values below.
For example - if the open pressure is 130 kPa at 100 kPa barometric, your open pressure at 65 kPa barometric would be 130 - (100 - 65) = 95 kPa.

7. Set the Test DC value to 10%, repeat the pull, make note of the boost you got, repeat for 20% 30% and so on up to about 1.2 bar of boost, but don't go over it. And set Test Enable to, well, enabled.
You use the values here to fill out the Base DC table, a pressure ratio of 2 is 2 times barometric pressure, pressure ratio of 2.5 is 2.5 times barometric pressure and so on. Create a math parameter in the log to figure out what the pressure ratio is.
Fill out the Base DC table according to the measured numbers. You can guess the values you didn't hit, that's fine, a PID loop in the ECU will fix small errors later anyway.

- Under Torque Management / SCTC Boost Control
8. When you're done filling out the Base DC table, set your Boost Max Limit to something just barely above the wastegate spring boost pressure and test it out!

You control the boost by RPM in the Knock Airmass table, don't keep it set to 1 g across! That's your Cylinder Airmass from the log file. It's the maximum value your ECU tries to reach. The Spark Retard axis is a protection that automatically changes the target airmass depending on how much knock you get.
When you set that up correctly, you can increase the whole Boost Max Limit table to 250 kPa and the ECU will automatically obey the turbo overspeed and efficiency tables, and vary the boost according to the ambient pressure and temperature and whatever.

The stock turbocharger does not like too much boost, my knock airmass table on the stock turbo with some mods looked like this, you can start from here

Attachment 125105

This is a general guide, and can be used for any kind of turbocharger install on your car! Worked fine for me installing a bigger unit.

Oh, and your Peak Torque, Brake Torque and Overboost tables can be set up to these values (Nm) across the range, don't overdo them, there's no point unless something is limiting you.
201.75 220.5 232.75 241.75 250 257 263 267.75 272.5 276.5 278.25 278.75 276 270 248.5 212.25

Add these to your log, too
Air-Fuel Ratio Commanded
Injector Pulse Width Bank 1 - used for Injector Duty Cycle math parameter, that one should never go above about 95%

I'm blown away by all that information! That's awesome! Thank you so much for taking the time to break that down for me! I tune a lot of GM v8 cars so i'm not super familiar with everything involved with the turbo adjustment parameters or how many tables are involved in the ecm. I've been trying to learn from posts and then thought I could grasp some things after seeing what ZZP changed when I had them do a tune off data logs. It helped a little but not as much as I had hoped. I find it interesting how you brought up the knock airmass table because I always wondered why they set that to all 1's when everyone else's tune on here that I saw always had decimal values. What you said makes complete sense now. I live in Ohio so no mountains here. lol. The weather looks like it should be nice tomorrow so hopefully I'll be able to go out and try this process and get things dialed in. Unfortunately I had already thrown away everything from the old turbo not thinking about checking that preload first. Seeing how the rod was threaded I should've known better. It is a factory replacement turbo but the factory is a Garret I believe and this is a Mahley turbo. Whenever I can finally get it handled I'll let you how it went and the results. thanks again!

Quote:

Originally Posted by sbarisic

Is it the same kind of turbocharger?

Here's what you do - undo everything you have done to the tune that ran just fine on the old turbo.

1. Check your wastegate actuator rod preload, should be about the same as the old one. Doesn't have to be that precise, but a good thing to check so it's not way off.

- Under airflow / turbocharger tab
3. Set your whole Base DC table to 0 and copy to Base DC Scav (my car doesn't use the Base DC Scav table at all so i just have it set at 0 all the time). Any value here below 0 or above 100 make no sense.
4. Make sure your underboost/overboost tables under diagnostics are not in your way.

5. Make a wide open throttle pull in a higher gear, 3rd for example, from very low RPM to the redline and log. You should see some amount of boost pressure - that's your wastegate spring boost pressure.

- Under airflow / turbocharger tab, again
6. Fill out the "Wastegate Open Boost" table at your barometric pressure (which i assume is 100 kPa unless you live on a mountain) to the measured wastegate spring boost pressure and guesstimate the values below.
For example - if the open pressure is 130 kPa at 100 kPa barometric, your open pressure at 65 kPa barometric would be 130 - (100 - 65) = 95 kPa.

7. Set the Test DC value to 10%, repeat the pull, make note of the boost you got, repeat for 20% 30% and so on up to about 1.2 bar of boost, but don't go over it. And set Test Enable to, well, enabled.
You use the values here to fill out the Base DC table, a pressure ratio of 2 is 2 times barometric pressure, pressure ratio of 2.5 is 2.5 times barometric pressure and so on. Create a math parameter in the log to figure out what the pressure ratio is.
Fill out the Base DC table according to the measured numbers. You can guess the values you didn't hit, that's fine, a PID loop in the ECU will fix small errors later anyway.

- Under Torque Management / SCTC Boost Control
8. When you're done filling out the Base DC table, set your Boost Max Limit to something just barely above the wastegate spring boost pressure and test it out!

You control the boost by RPM in the Knock Airmass table, don't keep it set to 1 g across! That's your Cylinder Airmass from the log file. It's the maximum value your ECU tries to reach. The Spark Retard axis is a protection that automatically changes the target airmass depending on how much knock you get.
When you set that up correctly, you can increase the whole Boost Max Limit table to 250 kPa and the ECU will automatically obey the turbo overspeed and efficiency tables, and vary the boost according to the ambient pressure and temperature and whatever.

The stock turbocharger does not like too much boost, my knock airmass table on the stock turbo with some mods looked like this, you can start from here

Attachment 125105

This is a general guide, and can be used for any kind of turbocharger install on your car! Worked fine for me installing a bigger unit.

Oh, and your Peak Torque, Brake Torque and Overboost tables can be set up to these values (Nm) across the range, don't overdo them, there's no point unless something is limiting you.
201.75 220.5 232.75 241.75 250 257 263 267.75 272.5 276.5 278.25 278.75 276 270 248.5 212.25

Add these to your log, too
Air-Fuel Ratio Commanded
Injector Pulse Width Bank 1 - used for Injector Duty Cycle math parameter, that one should never go above about 95%

I give up I have been trying to figure out how you are getting the 65kpa.

I did mine I am at 80 kpa and about 150 kpa on wastegate spting pressure..

I am trying to achieve 20 psi all the time it peaks out then falls. trying to figure out if its the wastegate or the bpv or just the back pressure in the exhaust opening the waste gate.

Ohh and zzp set my knock air mass to 1 as well. I wasn't really happy with them. I got into an argument with them about the throttle staying open.. and I lost all hope after that. I said the throttle is closing and he was like what you think it's supposed to stay open all the time? I said no but its not supposed to close. I ended up fixing it myself raising either the driver demand table or peak torque.. I cannot remember. I also wanted them to do the cams but he wouldn't because they fluctuate too much which I am sure they do but only so much...

1 Attachment(s)

Quote:

Originally Posted by danyilboon9

I give up I have been trying to figure out how you are getting the 65kpa.

I did mine I am at 80 kpa and about 150 kpa on wastegate spting pressure..

I am trying to achieve 20 psi all the time it peaks out then falls. trying to figure out if its the wastegate or the bpv or just the back pressure in the exhaust opening the waste gate.

Ohh and zzp set my knock air mass to 1 as well. I wasn't really happy with them. I got into an argument with them about the throttle staying open.. and I lost all hope after that. I said the throttle is closing and he was like what you think it's supposed to stay open all the time? I said no but its not supposed to close. I ended up fixing it myself raising either the driver demand table or peak torque.. I cannot remember. I also wanted them to do the cams but he wouldn't because they fluctuate too much which I am sure they do but only so much...

The 65 kPa is the theoretical barometric pressure in the example, so the absolute pressure of the air around you if you were on a mountain or something. It would be 101 kPa if you were at the sea level.

Attachment 125226

Here the wastegate open pressure for the turbo at 1000 RPM is 73.5 kPa - 0.735 bar - 10.66 psi.
Boost is calculated based on the ambient (also called barometric) pressure and the absolute pressure you get in the intake manifold. On 101.5 kPa ambient you get 175 kPa of absolute pressure in the intake manifold, and on 65 kPa ambient you get 138.5 kPa in the intake manifold - they both equal to 73.5 kPa of boost.
That means 101.5 kPa ambient + 73.5 kPa spring pressure at 1000 rpm = 175 kPa in the table.

The whole point of the wastegate open pressure table is to tell the ECU when to actually use closed loop boost control - it's the minimal boost pressure with a turbocharger that you can get at any RPM if you had long enough runway and load on the engine (long gear uphill, basically) so the ECU doesn't even try to lower it using the wastegate but using the throttle plate or whatever else.

Now, if you are keeping the wastegate 100% closed, and the boost keeps dropping at high RPM, that usually means the exhaust gasses create so much pressure in the exhaust manifold that they crack open the wastegate anyway.
You can probably put a stiffer spring in the wastegate actuator to keep it forced closed, but that also means you are increasing the minimum boost pressure you can get from the turbo AND straining the turbo above the region it was designed to operate in.

In the best case, the compressor becomes so much inefficient that you're actually losing horsepower with higher boost. The air heats up so much that the airflow stays the same while the boost keeps climbing, and above a certain threshold the turbo starts overspeeding, instead of 50'000 RPM more for 10 psi of boost more, you get 200'000 RPM more for only 1 psi of boost and the compressor wheel suddenly explodes.
This is operation to the right of the choke line and that damages the turbocharger!

Keep an eye on the mass airflow, you might be surprised to see higher numbers at lower boost pressures here. Any more boost above that is just wasted energy and strain on things.

In the Airflow - Turbocharger tab
33435 Surge Limit
334655 Efficiency
33468 Speed 2
33491 Pressure Ratio Max
3304 Overspeed Limit Min

These tables basically describe the compressor map for the turbo you are using. And if you are putting a bigger one, it would be a good idea to fill it out correctly.
The Overspeed Limit Min number enables the overspeed limiting, reaching airmasses above the one that you put in there makes the ECU obey the speed, choke and efficiency limits.

Basically what all of this means is you reached the size limitation of the turbo and it's time for a bigger one. ;)

I’ve been messing around with mine all week and it still leaves me baffled with the 13-15 degree of KR I keep getting until it warms up. After it warms up it still does but not as aggressively. I changed the plugs and the coil bc I was getting some misfires on cylinder 4 but that still didn’t fix it. The confusing part is it never did that before the replacement turbo.

I think I may need to do the wastegate spring pressure test again or I did something wrong. I set both DC tables to 0 and disabled the under/overboost diagnosis. At 1400 I was only getting 96-97kpa when the factory is 134kpa. Is that maybe a sign that the preload is wrong on the wastegate solenoid since I never checked it before I tossed the other one?

Quote:

Originally Posted by Jmaurer

I’ve been messing around with mine all week and it still leaves me baffled with the 13-15 degree of KR I keep getting until it warms up. After it warms up it still does but not as aggressively. I changed the plugs and the coil bc I was getting some misfires on cylinder 4 but that still didn’t fix it. The confusing part is it never did that before the replacement turbo.

I think I may need to do the wastegate spring pressure test again or I did something wrong. I set both DC tables to 0 and disabled the under/overboost diagnosis. At 1400 I was only getting 96-97kpa when the factory is 134kpa. Is that maybe a sign that the preload is wrong on the wastegate solenoid since I never checked it before I tossed the other one?

Hmm weird, can you move the wastegate rod by hand? Is it firmly closed when the car is turned off? You can also test it by applying pressure with an air compressor to it.

How does it behave at other RPM ranges?

The 13-15 knock retard when cold sounds also very strange, check your intake piping. There can be oil inside but it shouldn't be too much, and honestly, a new turbo shouldn't leak any oil at all.

Oh yes, did the turbo come with an oil restrictor installed?

Quote:

Originally Posted by Jmaurer

I’ve been messing around with mine all week and it still leaves me baffled with the 13-15 degree of KR I keep getting until it warms up. After it warms up it still does but not as aggressively.

At those levels of KR, I'd suspect "false knock" or some other mechanical noise causing the ECM to think it's knocking.

Quote:

Originally Posted by tunerpro

At those levels of KR, I'd suspect "false knock" or some other mechanical noise causing the ECM to think it's knocking.

I wouldn't count on it, whatever noise causes this should be resolved.

And another thing that should be checked are the spark plugs. They should have a 0.7mm (about 0.027'') gap.
The color of them could also indicate if something was wrong.

But that's about it that i can remember on the top of my head without a physical look at the car. Posting a tune and cold start log could be of help maybe.

The knock I thought I had figured out yesterday because it almost seemed like open loop KR and then once closed loop occurred it went away so I figured it must be some kind of correction but that wasn’t the case today. After I turn it on the second I touch the gas it will start yanking timing backing out of the driveway. Then just starting to move down the road it pulls a few degrees then just climbs up to 10+ with me barely on the gas. It will do that for the first 5-10 minutes of me driving. I run 93 octane and if my memory is correct I don’t think I’m even running higher than factory timing. 5 degrees lower in the high air mass areas too. I have the ZZP CAI and downpipe. I’ve noticed my O2 sensor has always been white, even after I replace it and the old turbo fins were solid white as well and slight white on the plugs. I just changed those out to coppers and I closed the plug to .025 to see if it helped with the KR but didn’t seem so . With NA cars the white tells me it’s extremely lean but I’m not sure if that correlates the same to turbo cars because no matter how much fuel I add to either the MAF or VVE table it just tries to pull it out anyway pushing trims -10+ so I’ve just adjusted it to where I bounce between -4 to -9. I lifted the rich swing voltage on the O2 sensor 100 mv the other day just to see what happened and it “seemed” like it may have helped but I’m still unsure.

2 Attachment(s)

here is a log with the KR and the tune that I have currently have in it.

Attachment 125350

Ah i think i see what's wrong. The ZZP cold air intake piping where the MAF sensor is - i assume it's a bigger inside diameter than stock? I can't seem to find any information on it online.

Try these values for the Maf vs. Frequency table, i added 15 percent everywhere compared to the base from the history in the tune file
And don't forget to undo the oxygen sensor voltages and dynamic airmass disable/reenable values before testing.

Code:

0 0 0 0 0 0 0 0 0 0 0 0 0 2.18410801887512 4.85923004150391 7.85934734344482 11.2312879562378 15.4193744659424 19.9866962432861 24.6486015319824 29.5619144439697 34.661060333252 39.9539451599121 45.4745254516602 50.9413108825684 56.5848083496094 62.0455932617188 67.4291839599609 72.7355651855469 78.0482406616211 83.1705551147461 88.1813812255859 93.0807113647461 97.8685607910156 102.544906616211 107.105041503906 111.559951782227 115.904411315918 120.13842010498 124.261985778809 128.275100708008 132.177780151367 135.970001220703 139.134231567383 142.729110717773 146.246643066406 149.68684387207 153.049667358398 156.335159301758 159.543304443359 162.674087524414 165.7275390625 168.703628540039 171.602355957031 174.423736572266 177.167785644531 179.83447265625 182.423828125 184.935791015625 187.370422363281 189.727737426758 192.007659912109 194.210250854492 196.335494995117 198.383377075195 200.353912353516 202.247085571289 204.062927246094 205.801422119141 207.46257019043 209.046356201172 210.552780151367 230.633377075195 234.461318969727 238.289260864258 242.117202758789 245.94514465332 249.773086547852 253.601028442383 257.428955078125 261.256896972656 265.084838867188 268.912780761719 272.74072265625 276.568664550781 280.396606445313 284.224548339844 288.052459716797 291.880401611328 295.708374023438 299.536285400391 303.364227294922 307.192169189453 311.020111083984 314.848052978516 318.675994873047 322.503936767578 326.331878662109 330.159820556641 333.98779296875 337.815734863281

You will need a wideband sensor to properly tune this one, unless somebody runs the same cold air intake assembly and is willing to share the MAF table.

EDIT:

If this is a 3'' inside diameter right now, and i think the original is 2.5'', then you need to rescale the whole table by (3 / 2.5) = 1.2 or about 20% more

Quote:

Originally Posted by sbarisic

I wouldn't count on it, whatever noise causes this should be resolved.

I said "suspect" not "assume". :). But, yes, whatever is causing this needs to be investigated and resolved.

Unless I'm missing something.....

Stoichiometric fuel ratio along with lots of timing will give you a shit load of KR under load.

2 Attachment(s)

Quote:

Originally Posted by sbarisic

Ah i think i see what's wrong. The ZZP cold air intake piping where the MAF sensor is - i assume it's a bigger inside diameter than stock? I can't seem to find any information on it online.

Try these values for the Maf vs. Frequency table, i added 15 percent everywhere compared to the base from the history in the tune file
And don't forget to undo the oxygen sensor voltages and dynamic airmass disable/reenable values before testing.

Code:

0 0 0 0 0 0 0 0 0 0 0 0 0 2.18410801887512 4.85923004150391 7.85934734344482 11.2312879562378 15.4193744659424 19.9866962432861 24.6486015319824 29.5619144439697 34.661060333252 39.9539451599121 45.4745254516602 50.9413108825684 56.5848083496094 62.0455932617188 67.4291839599609 72.7355651855469 78.0482406616211 83.1705551147461 88.1813812255859 93.0807113647461 97.8685607910156 102.544906616211 107.105041503906 111.559951782227 115.904411315918 120.13842010498 124.261985778809 128.275100708008 132.177780151367 135.970001220703 139.134231567383 142.729110717773 146.246643066406 149.68684387207 153.049667358398 156.335159301758 159.543304443359 162.674087524414 165.7275390625 168.703628540039 171.602355957031 174.423736572266 177.167785644531 179.83447265625 182.423828125 184.935791015625 187.370422363281 189.727737426758 192.007659912109 194.210250854492 196.335494995117 198.383377075195 200.353912353516 202.247085571289 204.062927246094 205.801422119141 207.46257019043 209.046356201172 210.552780151367 230.633377075195 234.461318969727 238.289260864258 242.117202758789 245.94514465332 249.773086547852 253.601028442383 257.428955078125 261.256896972656 265.084838867188 268.912780761719 272.74072265625 276.568664550781 280.396606445313 284.224548339844 288.052459716797 291.880401611328 295.708374023438 299.536285400391 303.364227294922 307.192169189453 311.020111083984 314.848052978516 318.675994873047 322.503936767578 326.331878662109 330.159820556641 333.98779296875 337.815734863281

You will need a wideband sensor to properly tune this one, unless somebody runs the same cold air intake assembly and is willing to share the MAF table.

EDIT:

If this is a 3'' inside diameter right now, and i think the original is 2.5'', then you need to rescale the whole table by (3 / 2.5) = 1.2 or about 20% more

Attachment 125424 Attachment 125425

Quote:

Originally Posted by sbarisic

Ah i think i see what's wrong. The ZZP cold air intake piping where the MAF sensor is - i assume it's a bigger inside diameter than stock? I can't seem to find any information on it online.

Try these values for the Maf vs. Frequency table, i added 15 percent everywhere compared to the base from the history in the tune file
And don't forget to undo the oxygen sensor voltages and dynamic airmass disable/reenable values before testing.

Code:

0 0 0 0 0 0 0 0 0 0 0 0 0 2.18410801887512 4.85923004150391 7.85934734344482 11.2312879562378 15.4193744659424 19.9866962432861 24.6486015319824 29.5619144439697 34.661060333252 39.9539451599121 45.4745254516602 50.9413108825684 56.5848083496094 62.0455932617188 67.4291839599609 72.7355651855469 78.0482406616211 83.1705551147461 88.1813812255859 93.0807113647461 97.8685607910156 102.544906616211 107.105041503906 111.559951782227 115.904411315918 120.13842010498 124.261985778809 128.275100708008 132.177780151367 135.970001220703 139.134231567383 142.729110717773 146.246643066406 149.68684387207 153.049667358398 156.335159301758 159.543304443359 162.674087524414 165.7275390625 168.703628540039 171.602355957031 174.423736572266 177.167785644531 179.83447265625 182.423828125 184.935791015625 187.370422363281 189.727737426758 192.007659912109 194.210250854492 196.335494995117 198.383377075195 200.353912353516 202.247085571289 204.062927246094 205.801422119141 207.46257019043 209.046356201172 210.552780151367 230.633377075195 234.461318969727 238.289260864258 242.117202758789 245.94514465332 249.773086547852 253.601028442383 257.428955078125 261.256896972656 265.084838867188 268.912780761719 272.74072265625 276.568664550781 280.396606445313 284.224548339844 288.052459716797 291.880401611328 295.708374023438 299.536285400391 303.364227294922 307.192169189453 311.020111083984 314.848052978516 318.675994873047 322.503936767578 326.331878662109 330.159820556641 333.98779296875 337.815734863281

You will need a wideband sensor to properly tune this one, unless somebody runs the same cold air intake assembly and is willing to share the MAF table.

EDIT:

If this is a 3'' inside diameter right now, and i think the original is 2.5'', then you need to rescale the whole table by (3 / 2.5) = 1.2 or about 20% more

Why not just tune the maf ?? its easy I can show him mine but I am at 6k feet and on e85

Quote:

Originally Posted by danyilboon9

Attachment 125424 Attachment 125425

So the stock one is 63.45 and the ZZP one is 71.16? That's close to the estimated 15% nice.

Quote:

Originally Posted by danyilboon9

Why not just tune the maf ?? its easy I can show him mine but I am at 6k feet and on e85

You can't tune anything fuel related without a wideband sensor. And OP did not mention he has one.

As for your MAF table, yes it will work just fine on another car as long as the air filter assembly and MAF location and piping diameter is identical.
And if it has been tuned properly, that is if the car requests for example 0.8 Lambda and the wideband actually reads 0.8 Lambda (I am deliberately not using AFR units here).

The fuel and elevation do not matter. That's the beauty of the mass airflow - as it measures the actual mass of air entering the engine. So it's automatically compensating for pressure and air temperature.
Fueling then takes the measured and filtered mass of air, the stoich value for the fuel you're using and calculates the proper proportion of the fuel mass for injection.

1 Attachment(s)

63.45 is with the insert and 71.16 is just the tube.. The intake has an insert you can remove if needed.

I do not have a wide band on this car. So far I’ve just scaled the MAF using the trims. I know the wide band is the best way but other than this car when I use the trims with other cars the car dials in pretty nice. With this car no matter how much I scale it it just removes what I add to it which is what drives me nuts about the signs of it being lean on the sensor and turbo. It’s like this car wants to run lean and that’s why I started messing with the O2 voltage in the tune. Correct me if I’m wrong but if I dialed it in with a wide band wouldn’t the ecm just go right back to pulling fuel to the incorrect ratio it’s trying to hit? I’m going to toss your updated MAF table in later today and see how it goes. I have a very chaotic schedule so I can’t always hop on here or mess with it so I appreciate your continued help! And I did mess with waste gate rod and it is pretty firm. Without pulling off the heat shield I can’t get it to move.