B8 A4 2.0T K04 Tune ZF8 93 Octane

[Klajdi]

Hey everyone,

I want to use this thread as a place to document and share my tuning journey on my 2012 Audi A4 zf8.

I'll update whenever I make decent progress on the iterations of the tune, but I am a full time student so the progress might not be the most consistent. I started tuning with HP tuners after trouble with IE's tunes for this platform and decided to make a custom tune to avoid the trouble of off the shelf tunes.

This is the progress I have so far. I am currently still working with my wastegate duty cycle and boost tuning after recently changing my wastegate spring.

2012 Audi A4 prestige quattro 2.0t (V0.08).hpt
v.08 Launch 2012.A4.Zf8.K04.IC.DP short.hpl


These tunes are provided as-is and were made for my personal vehicle. They may not be safe or compatible with other vehicles, even if on the same platform. I am not responsible for any damage or malfunctions resulting from their use. Use at your own risk.

[TylerJDubbs]

I have attached a channel file for the logger, please relog with this channel file loaded into the beta VCM Scanner

B8-New.Channels.xml

A couple changes I don't like... the wastegate control changes you made to filtering and compensation, non of that is needed. the changes to MAF correction tables, non of that is needed and is actually causing you to lean out at WOT +25%STFT in logs.... The desired throttle pressure ratio axis data, this is not needed but i don't even think it does anything different the way you set it up. the way you setup your [ECM] 32850 - Torque to Load is interesting, i would really only modify the highest 4 cell rows (50-90% torque area) and this needs to be reflected in your [ECM] 32900 - Optimum Engine Torque. for fueling if you want to run only in PE you'll need to FF (set at 1263*C)[ECM] 14995 - Exhaust Manifold EGT Threshold Temperature so that temp control fueling is disabled, otherwise you're looking at running as rich as .70 when in higher load. as for the HPFP control if you want to run 170bar like your homogenous request map sugests you will need to raise [ECM] 15209 - High Pressure Fuel Maximum Desired Pressure to 170 as well, if you want my recommendation on pressure i would run the stock 150, or 158bar if you want a touch extra

i would also reccomend you have a look at the stage 2 files i posted here from my early days, non of it is perfect but it might give you a better idea of how to set some of the tables up

https://forum.hptuners.com/showthrea...4-91Oct-(2011)

[Klajdi]

Thanks for the reply!

I have included a new tune and log based on your recommendations.

I made the changes mentioned above and updated some of the spark and cam angle tables using the tunes in your thread as guidance. The adjustments to optimum engine torque and torque to load helped greatly with drivability, but now I am dealing with absolute load not meeting my desired load in some cases, maybe due to incomplete optimization of the boost control tables? Also, the desired load seems to be less than what I was going for when creating my torque management tables, so I am currently going through trying to figure out if there are any other limiting tables in terms of boost pressure or issues with the range of axis values regarding load in other places of the tune. Overall the tune feels more legitimate and my logs match my expected results more closely without any strange behavior, but it has a ways to go in terms of performance.

Are there any obvious errors that would lead to my issues with underloading, or is it simply a boost tuning issue?

2012 Audi A4 prestige quattro 2.0t 93 Octane Revised.hpt
93 octane- Corrected 1st-3rd gear pull.hpl

[TylerJDubbs]

Thanks for the reply!

I have included a new tune and log based on your recommendations.

I made the changes mentioned above and updated some of the spark and cam angle tables using the tunes in your thread as guidance. The adjustments to optimum engine torque and torque to load helped greatly with drivability, but now I am dealing with absolute load not meeting my desired load in some cases, maybe due to incomplete optimization of the boost control tables? Also, the desired load seems to be less than what I was going for when creating my torque management tables, so I am currently going through trying to figure out if there are any other limiting tables in terms of boost pressure or issues with the range of axis values regarding load in other places of the tune. Overall the tune feels more legitimate and my logs match my expected results more closely without any strange behavior, but it has a ways to go in terms of performance.

Are there any obvious errors that would lead to my issues with underloading, or is it simply a boost tuning issue?

2012 Audi A4 prestige quattro 2.0t 93 Octane Revised.hpt
93 octane- Corrected 1st-3rd gear pull.hpl

These logs actually look good now! No throttle cut, boost is tracking close but also wastegate duty is capped out, nothing more you can get out of the turbo without mechanical adjustments

Looking pretty rich in WOT, I would target around .82 lambda at the richest in PE, i would also return the low pedal/torque areas back to 1.000 lambda for efficiency while cruising, your tuning of the PE table should look like stock with just richer values in the high pedal areas, like this 9159d7cd-dd44-4d44-89c3-99f1df0e10d7.jpg

also your base tip should be what the turbo makes for boost without any WGDC (Set max WGDC to 0% to calibrate this)

what K04 do you have?

[Klajdi]

I have a ko4-106. I bought the turbo from a friend, so I don't know exactly what it is, but I suspect its a F23L.

I got the values for the base TIP table by datalogging with the wastegate locked at 0% under high load driving and full throttle in higher gears... but I was using the actual TIP channel and forgot to subtract barometric pressure lol. The tip base values make a lot more sense and correlate better to the current crack pressure after I corrected that. I have a forge wastegate (FMACA4L) because I couldn't get the boost pressure I was looking for with the original wastegate, and currently I have the blue spring installed (rated on their website for "Blue – running pressure 18 psi (1.2 bar) - spool up/running pressure 14 psi (0.95 bar)" , but I'll try increasing the crack pressure a bit to see if I can fix the boost issue. Currently, in higher gears (4th) I am surging around 3200 RPM when WOT from low rpm, causing throttle to cut back. My first instinct is to adjust my CAN desired pressure in higher gears as the turbo has more time to spool, but I'm curious if it is important to also adjust my PR limits at this RPM as it seems that the turbo is hitting a physical limit.

I understand that generally a lambda of about 0.85 is optimal for power, but it was my assumption that a richer lambda would help reduce knock and allow for more spark advance, particularly on turbocharged applications with higher IAT. How did you settle at 0.82 lambda? Is this something that generally works across the 2.0T or is it dependent on the specific modifications done?

I'll adjust my crack pressure, TIP pressure, WG CAN pressure in higher gears, PE table, and report back with my updated tune and data logs after a couple iterations and retuning the TIP base pressure for the new crack pressure.

[TylerJDubbs]

I have a ko4-106. I bought the turbo from a friend, so I don't know exactly what it is, but I suspect its a F23L.

I got the values for the base TIP table by datalogging with the wastegate locked at 0% under high load driving and full throttle in higher gears... but I was using the actual TIP channel and forgot to subtract barometric pressure lol. The tip base values make a lot more sense and correlate better to the current crack pressure after I corrected that. I have a forge wastegate (FMACA4L) because I couldn't get the boost pressure I was looking for with the original wastegate, and currently I have the blue spring installed (rated on their website for "Blue – running pressure 18 psi (1.2 bar) - spool up/running pressure 14 psi (0.95 bar)" , but I'll try increasing the crack pressure a bit to see if I can fix the boost issue. Currently, in higher gears (4th) I am surging around 3200 RPM when WOT from low rpm, causing throttle to cut back. My first instinct is to adjust my CAN desired pressure in higher gears as the turbo has more time to spool, but I'm curious if it is important to also adjust my PR limits at this RPM as it seems that the turbo is hitting a physical limit.

I understand that generally a lambda of about 0.85 is optimal for power, but it was my assumption that a richer lambda would help reduce knock and allow for more spark advance, particularly on turbocharged applications with higher IAT. How did you settle at 0.82 lambda? Is this something that generally works across the 2.0T or is it dependent on the specific modifications done?

I'll adjust my crack pressure, TIP pressure, WG CAN pressure in higher gears, PE table, and report back with my updated tune and data logs after a couple iterations and retuning the TIP base pressure for the new crack pressure.

Hmmm okay, this turbo is only flowing like 240g?s with the WGDC at max, just seems a bit low to me

The .82 was just a suggestion, In reality .78-.84 will work fine, just .75 is way too rich to see any substantial gains, and hard on the wallet when at the pump lol

When it comes to the value in the TIP base map those are absolute pressure, should be no calculations needed? if you run 1.6bar absolute on ?Waste-gate only? the values in that table should be 1.6bar at every RPM the turbo is able to make that pressure.

For boost control on this binary I would switch the substitute waste-gate control to enable and use the waste-gate substitution map to tune your DC, it?s a lot easier than the stock feed forward boost control. You will need to populate the last row of numbers as this is set to 0% from factory

[Klajdi]

What MAF numbers should I be seeing on ko4? Online im seeing around 280 g/s. I am running a 3 inch downpipe but stock exhaust after that so that's the main restriction can think of. Although boost drops off in the higher rpm so maybe that can cause some of the 40 g/s discrepancy?

Regarding the TIP base map, I thought it was absolute at first too, but in the VCM editor it says " [ECM] 34911 - TIP Base Pressure: Defines how much the base TIP will be over barometric pressure when the wastegate is commanded open. This will correspond to wastegate spring pressure typically.". I adjusted the wastegate already so I will do a datalog with the wastegate locked and send it just for reference.

[Klajdi]

WG locked, adjusted crack pressure (TIP datalogging).hpl

I locked the WG in the tune and went out and did some logging after adjusting my wastegate to be tighter. I updated the TIP base table based off the values at each rpm in the data log and these are the results:
TIP base table.png

[TylerJDubbs]

looks good for wastegate, enable substitution and turn it up lol