Magnuson supercharger + smoothboost with factory E92 as PWM boost controller

Hey all

I would like to post about an experiment I have just successfully finished.
I have a 2016 Camaro SS with a Magnuson supercharger on it. I recently finished the addition of a smoothboost controller which i have wired to the E92 ECM and have enabled the boost control functionality
I have seen previous posts how this is not possible, and you need the ZL1 OS to make this work. This is simply not true.
There are a good amount of hurdles, however it is very much possible.

With this change, The Driver Demand tables along with Torque tables will be what the computer uses to determine how much boost to employ at any given Torque Request
This provided me with a much more linear pedal.

At this point there are a few tuning points that I must make to any looking to follow this template.
I offer this Post in good faith, and I can not make promises of the completeness of the tuning advice or hold any liability
This requires re wiring the E92 ECM, if you are not comfortable with pin configurations or soldering this may not be for you.
There is a real risk of damage to your motor and ECM if pieces are not done correctly here.
There may still be pitfalls to this method that I have not ran into yet.
I can not confirm if this method holds true in different scenarios

E92 Wiring Changes:

Move from:
X1 -- 4 YE/WH 3200 Throttle Inlet Absolute Pressure Sensor Signal
X1 -- 5 Throttle Inlet Air Pressure Sensor Control 5V
to
X2 -- 45 YE/WH 3200 Throttle Inlet Absolute Pressure Sensor Signal
X2 -- 64 Throttle Inlet Air Pressure Sensor Control 5V

Add Supercharger inlet pressure signal
This sensor is a standard 1 Bar Map sensor that is placed After the throttle body, before the Roots
X1 -- 5 Super Charger Inlet Air Pressure Sensor Control 5V
X1 -- 20 Super Charger Inlet Air Pressure Sensor Low Reference
X1 -- 4 Supercharger inlet pressure signal

Add Supercharger Temperature sensor
In the LT4 context, this sensor is combined with the main MAP sensor on the back of the blower
X1 -- 13 Induction Air Temperature Sensor 2 Signal
The IAT 2 Sensor uses the same ground as the Main MAP sensor
X2 -- 63 Manifold Absolute Pressure Sensor Low Reference

Add boost control PWM output signal
X2 -- 71 BN/YE 258 Waste Gate Solenoid Control

Wire (X2 --71) to the Negative wire of the Smoothboost PWM controller
One can pull 5v from X1-17 on the ECM to provide a reference voltage to the smoothboost PWM controller
X1 - 17 Barometric Pressure Sensor 5V Reference

(Note: using the smoothboost 5v PWM controller will result in P0033 and P0034 being present the factory Zl1 boost control actuator shouldnt have this issue )

First you must have enabled SC-SCIAP-TIAP in the sensor config. Along with adding the IAT2 and SCIAP sensor wires into the ECM.
Under Engine -> Airflow
Sensor Config: SC-SCIAP-Tiap
Configure IAT 2 Sensor Cal

From my experience IAT2 sensor is automatically picked up with these changes. And may be picked up without this change

SCIAP will be configured by

[ECM] 4013 - Supercharger Inlet Air Pressure Sensor Linear:
[ECM] 4014 - Supercharger Inlet Air Pressure Sensor Offset:

At this point, I suggest ensuring the vehicle still starts and runs. A good minimal viable point.

You may need to re tune your VVE/MAF config to prevent Airflow DTCs.
The Factory Boost controler is very specific about DTCs being enabled and functioning correctly

The next section will be to enable the boost controller.
Alot of this section was copied straight from a Zl1/LT4 Tune file
Under Engine -> SC/TC General

(IAT2 is required for Type Fitted to be set to Supercharger)
Set "Type Fitted" to Supercharger,
Set Actuator Type to SC Bypass
Set the Actuators to DC Motor.

Under Engine -> Airflow Turbocharger
**Set BOV/BPV to Enable**
Set **Wastegate Open Boost** to the current Max kpa from the blower, My example is 140 kpa
Configure Speed map to match the supercharger spin speed (I copied Zl1 Values Here)
Configure **Pressure Ratio Max limits** (and column axis if needed).


The Boost control Code is very sensitive to Any Airflow DTC's
Even if they are disabled, They will cause the boost controller to not allow any boost to build.
Especially the P101 P106 P0121 Tests must be enabled.
Also P0068 and P1101 must run and not produce any errors

I Always Suggest Keeping All vehicles Emissions compliant and never disabling any DTCs

The Key that i found That i could not find mentioned anywhere on the innerwebs:
Attachment 124785
The intercooler Circuit Must not throw an error.
Under System ->Coolant Pumps --> Intercooler
Set To Fitted
Set Enable Conditions to never be enabled
(unless one wishes to install a intercooler pump and have it controlled (not tested))

At this point in VCM scanner
(you may have to repoll for parameters)
Log these Parameters

- Desired boost
- Boost Duty Cycle
- Boost Torque

To prove all the main enable parameters are correct, you should be able to at this point, with the engine on and idling
open up "Vehicle Controls" in VCM Scanner
set the desired boost high, This should change the Boost duty cylce to 0 from ~100
Reset Desired boost on Vehicle Controls, i would not recommend driving with manual control enabled.
From here, There may be more tuning required.
Proceed at your own risk. There is no warranty implied here, I claim no responsibility for any mis configured catastrophes

3/10/2023 Update!
The enable switch for P0033 P0034 and P0035 diagnostics also must be thrown to complete this setup.
There is also in existence a IAT2 Enable switch, whiich im still unsure if is needed or not for this to work properly
They are not currently in the VCM suite

I have located this switches for the 2016 camaro ss, and will locate it in other tune files on request.



Meta Data

- 2016 Camaro SS
- OS: = E92 12673677
- Magnuson Supercharger 2650
- Smoothboost controller (With PWM addition)

Wow, kudos to you for trying this! I’m running the Smoothboost EBC on my Kong-ported Whipple 2.9 and found it to improve the drivability big time. Makes the pedal more linear and helped a lot at cold idle since I have a decent sized cam. Would love to be able to control boost by gear…. In any event, best of luck with this project! Hope you’ll keep us updated.

Very cool.

Curious if you have tried it with the SCIAP sensor installed alone first.. then the smooth boost.

Quote:

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Originally Posted by Alvin

Very cool.

Curious if you have tried it with the SCIAP sensor installed alone first.. then the smooth boost.

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I did not :( that was a Fail safe plan incase i couldnt get the ECM to control it.
I did do some testing with just the SCIAP sensor before jumping into the smoothboost part, and was very pleased with the throttle linear-ness, but without the smoothboost it still surged slightly as boost came in.

An update on this.

P0101 is a pain!

I think there is something missing in hptuners for manifold volume calculations when SCIAP is involved.
To add to that, vcm suite for E92 previously did not have the P0101 Max airflow delta adjustments.

Long story short, I got familiar with winols (demo) and Ghirda de compiler and found the P0101 max airflow delta table.
I had hptuners support add this table in after providing the xdf file, and i am planning on testing it this weekend!

ECM 14020 should be available for the E92 6.2L Camaro's now.

While looking for the table i found a few dynamic air manifold volume constants that look suspiciously like they need to be adjusted as well.
I am hoping this leads to the reason the airflow delta is going out of spec.

Im going to continue hunting for the root cause of the p0101, P1101 and P012B codes by comparing source on a LT4 calibration file.

Very cool!

I found out something very interesting

When you activate the SCIAP sensor, and in the VCM scanner, the 'supercharger inlet pressure' value is stuck at 0, This indicates that the linear and offset for the SCIAP sensor are not set.

At first I thought that this sensor was tied to AAP 2. however, from some code digging and parameter searching i found out that it is actually a completely separate sensor configuration with its own linear and offset.

I Sent the XDF file to Hptuners support, and hopefully they can add this for everyone.

Edit:

The SCIAP Inlet pressure sensor Linear and offset have been added to the VCM suite beta

[ECM] 4013 - Supercharger Inlet Air Pressure Sensor Linear:
[ECM] 4014 - Supercharger Inlet Air Pressure Sensor Offset:

I'm wonder if this would still work without the addition of the smooth boost valve, I assume so, maybe Alvin can chime in.

With the addition of the IAT 2, would it be appropriate to plug the factory IAT harness back into the MAF and plug the new IAT 2 harness into the sensor on the blower?

You had mentioned using the main map ground for the IAT 2, do you know what pin that was, or did you just splice into the wire?

Finally, I wish I still worked for GM if only to have access to all the wiring schematics. That said, does anyone know if the truck wiring is the same as the cars as it pertains to this?

Yeah it will work without smooth boost.

I've never added IAT 2

Hey,

With IAT2, yes you can plug the MAF plug back in.
IAT2 needs to be on the supercharger outlet side (boost side)

Here is the MAP sensor ground reference

X2 -- 63 Manifold Absolute Pressure Sensor Low Reference

I think as it pertains to this functionality, the wiring would be the same. I have not checked them all...
May be a delta between E92 and E92a potentially ?

Excellent thanks guys. Have you noticed ?max engine torque? increase to higher numbers with this addition? I would assume so.

Also, any recommendation on where to buy the ECU terminal pins or are they pretty much all the same quality?

We have them.. I'm sure many others do too. Its the same ECM pin as a E67 and E38. We intend to have a harness pigtail/with ECM pins on our website soon. I just haven't gotten around it.

Quote:

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Originally Posted by Alvin

We have them.. I'm sure many others do too. Its the same ECM pin as a E67 and E38. We intend to have a harness pigtail/with ECM pins on our website soon. I just haven't gotten around it.

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Good deal bud. Would you guys be selling them with a length of wire crimped as well?

BTW, do you recall if the pinouts on the trucks are the same as the cars for the added map sensor?

EDIT: I found a schematic for a 14 Silverado, and it would seem the pinouts are the same, the only difference is X1 pin 13 is for ambient air temperature. Does the ECU reference X1 pin 13 for Induction Air Temperature Sensor 2 Signal after changing MAP config to SCIAP? If so, what happens to the ambient air temperature reference? Does it just not look for this value anymore?

I dont know any details on pin out on the trucks.
I would have assumed it was the same untill you mentioned that..

In other news, I have been fighting the P012B error.
I found what appears to be a SCIAP performance table.
I dont quite have a good understanding of what it does or what the axis are.
This same table on the ZL1 is vastly different, which is a good hint to me that it needs to be added to VCM suite.
When set to the ZL1 configuration it allows the P012B error to clear when idling, but any throttle will throw it.

I think this is because of the remote mounting of the SCIAP Sensor, but have not had the time to test the sensor mounted straight to the inlet.
Which would be caused by the 'stall counters' as the vaccum travels through the hose being not as prompt as the ECM expects it to be.

If anyone has user-defined parameters that would also like to test the xdf file, and try out getting the P012B error solved, PM me, and i'll see if we can get the table found in your tune.
I also found what appears to be an Airflow Model table, which would be handy for the P1101 errors.

Quote:

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Originally Posted by GPGTP

Excellent thanks guys. Have you noticed ?max engine torque? increase to higher numbers with this addition? I would assume so.

Also, any recommendation on where to buy the ECU terminal pins or are they pretty much all the same quality?

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Max engine torque shouldnt have to change with this.
That should be the same regardless of if it is in SCIAP mode or not

I got pins from a junk yard, cut the ECM right out.

Quote:

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Originally Posted by GPGTP

Good deal bud. Would you guys be selling them with a length of wire crimped as well?

BTW, do you recall if the pinouts on the trucks are the same as the cars for the added map sensor?

EDIT: I found a schematic for a 14 Silverado, and it would seem the pinouts are the same, the only difference is X1 pin 13 is for ambient air temperature. Does the ECU reference X1 pin 13 for Induction Air Temperature Sensor 2 Signal after changing MAP config to SCIAP? If so, what happens to the ambient air temperature reference? Does it just not look for this value anymore?

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We didn't do anything with IAT 2 when I did the last one.

Email [email protected] ask about a SCIAP kit. I'm sure they can put something together quick for you.

Update!

I found the parameter that was causing the P012B, P0101 and P1101 with SCIAP enabled!!
Along with the Supercharger Inlet Performance Table (which i have not fully confirmed yet)

In the LT1 Vehicles it is set at 5.00
But in the LT4 Vehicles it is set around 83000.
It is sitting right before the manifold volume variables in the binary file, for anyone looking

I dont fully understand what the math in the code is doing at this point, however there is a calculation that is done during transient periods with the SCIAP sensor enabled.
This calculation is what is causing the dips in Supercharger inlet vacuum on any kind of pedal input as far as i can figure out.
I copied the LT4 Configuration on my vehicle and all the error conditions went away.

Once i can get a bit more information on these parameters I will send them in to Hptuners to be added to the suite.

Very cool discovery!

I haven't had any codes pop up with the SCIAP retrofitted in, and the PID reads correctly in the scanner, but I'm interested to dig in further.

Quote:

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Originally Posted by pisces_0

Very cool discovery!

I haven't had any codes pop up with the SCIAP retrofitted in, and the PID reads correctly in the scanner, but I'm interested to dig in further.

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What year/model/os are you running?
Maybe certian vehicles came with some of the behind the scene parameters already populated.

Also, can you confirm/Experiment that the P012B error is enabled in the DTC list?
Without that error specifically enabled, the weird dips in Supercharger Inlet Vaccum dont appear.
All you should need to do is start and idle the vehicle for the error condition to run

Quote:

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Originally Posted by will_974

I dont fully understand what the math in the code is doing at this point, however there is a calculation that is done during transient periods with the SCIAP sensor enabled.
This calculation is what is causing the dips in Supercharger inlet vacuum on any kind of pedal input as far as i can figure out.

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That smoothboost would have been nice to have/know about when I built my twincharged setup lol.

Sounds like your pressure sensors may not be configured properly though... Sensor measurement isn't considered trustworthy until it passes necessary diagnostics, P012B in your case. And based on your description, it sounds like you don't have a baro sensor installed...so I'm curious what the baro variable is doing. A data log would tell a lot.