I have a supercharged Cobalt and a 2.4l HHR. I recently discovered that the E67 controller in my HHR has supercharger controls (under Torque Management in the Engine group). Upon further research I found that the E67 is used to control some supercharged applications, most notably the supercharged 4.4L Northstar V-8 with VVT!

So I then compared the pins on the ECM connectors between the 2.4L HHR and Cobalt to the Cadillac STS with the LC3 supercharged Northstar and found enough commonalities to guess at a good connector configuration that could be used with the LSJ. Based on past experience with "creative rewiring", I have a high degree of confidence this would work.

The E67 has several tantalizing advantages over the P12, I think. First, it is a fully modern controller that is faster, and it fully uses GMLAN rather than Class 2 (like the P12). It offers two tables for MAF calibration, allowing higher frequencies to be read than the P12 and better resolution for lower frequencies. The fuel cutoff (if you've ever revved a 2.4L) is far more gentl than the P12's. The E67 has the Cylinder Charge Temperature adjustment features, which can help better approximate the charge air temperature inside the cylinders. The more sophisticated VE and speed density systems can greatly enhance airflow estimation (though tuning it can be a pain).

The only big thing I see missing is that the boost gauge is driven by the P12 controller via a pinout; I cannot see if there is a similar pinout on th E67. And besides that there would be no way to properly set the output voltages corresponding to the charge air boost/vacuum pressures. The gauge on the new Turbo Cobalts and HHRs use an ECM pinout also, but the dial's different scale means different voltages on the output wire for different pressure/vacuum pressures. I once obtained a gauge for the new SS and tried to use it in my supercharged SS, but it did not read the correct values. It was clear that the needle moved to the same physical location as it did on my gauge from the superchaged car.

Here's the thing that is truly interesting: a "hybrid" LSJ engine incorporating VVT. I'll bet you could use the new VVT 2.2L as a basis to do just that. Just consider that the 2.2L engine gained over 10 HP when it went to VVT in efficiency gains (mostly) from using VVT technology. Of course, this introduces the cam offset variables into the VE equasion, turning it from a 2-variable system into a 4-variable system. I have created a Mathcad worksheet that should be able to calculate the correct values for the full equasion (15 coefficients!), but it requires a good amount of log data to perform multivariate polynomial regression with.

I put this out in case anyone here has ever considered this. I have the Excel spreadsheet I created that details the connector pins for the ECU. The VVT idea is a pie-in-the-sky kind of thing; I think the ECU is worth looking at even without a major hardware change like that. But I'm a crazy tech head who enjoys problems like this.

Right now I don't have an extra ECU or the desire yet to rewire my ECU connectors in the engine bay (I'm already working on a big rebuild project), but if anyone out there had the time and the inclination, I'd be happy to lend any information I've gathered on the subject. I submit this for your consideration as an intellectual exercise, but hopefully at some point it will be a real endeavor. Enjoy!

BTW: The Excel spreadsheet can be found at the post I made in HP Tuners.

 

I've discovered more, and I am more convinced that this can work. The only hardware difference I've found that requires work is that the LSJ crankshaft sensor would have to be replaced with the sensor from the LE5.

The LSJ sensor produces an AC signal, but the LE5 produces a 5V pulsed signal. An extra wire for the CKP 5V Reference would need to be added into the harness. and the connector on the LSJ harness would need to be changed for the one on the LE5 harness. However this is not too difficult; if that is all I'd need to change on the harness, that's not bad at all.

I've edited the HP Tuners post to replace the Excel file with the latest updated version.

 

Im pretty sure the reluctor (sp) wheel is different on the cranks which doesnt allow them to be interchanged..

 

For my European, now supercharged, 2,2 we have very limited tuning possibilities over here and I was thinking of converting it to a "stand alone" P12 with HP tuners. (Needs crank trigger change etc. etc., but P12 can run my engine without Anti Theft system and the original in-car computer => Good!)
How is that with this E67 Ecu? Fully unlocked with HP tuners? Anti theft and other gubbins can be switched off to run only the engine like a stand alone ecu?

 

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I do believe VATS can be disabled, but I am not sure it would work as a full standalone. It still communicates with other modules using GMLAN such as the EBCM (brakes) and BCM. However, if the European version is not that different it could probably be made to work. If worse comes to worse, you could probably do some wiring work and replace things like the BCM with units from North American models. I've done some things like that before; it's just a matter of finding the right way of tricking the modules to work together. The most important part is the VIN for modules that require it to be encoded (the BCM, EBCM, and SDM I think primarily). For example, to get the E67 to work I will have to encode my modules with a 2006 or 2007 2.4L VIN.

To address the reluctor wheel, they are both 58X, and the sensor position is the same. While I don't discount the possibility that you are right about the reluctor wheel, I think there is a good chance that the actual reluctor wheel is the same in both engines. The wheel is not much more than a notched gear-looking device on the crankshaft, basically just a piece of metal with 58 notches in it. The notches are spaced at 1/60 rotation intervals; there are 58 because notches are missing (or larger, I forget which) in one spot to indicate where the reference point of the shaft rotation is. The sensors themselves appear to be the same size and shape, and they also appear to fasten into their respective engine blocks at the same locations. While again I am not 100% certain of this, evidence strongly suggests the only difference is the kind of signal they produce. GM has transitioned in many cases from analog to digital signalling; the P12 receives an analog signal (an AC waveform) while the E67 receives a DC pulse (digital waveform) signal.

Incidentally, I've discovered that the E67 underwent some significant changes between 2006 and 2007 that open the gates to boosted applications. In 2006 the injector flow rates could only be mapped to a maximum of 11 or 12 PSI of boost. In 2007, an entirely different system maps injector flow rate to a pressure differential between the fuel pressure and manifold pressure, and the range is much greater than before. It seems to coincide with the added application some vehicles have of a fuel pressure control module (FPCM), though it still uses the new mapping methodology for vehicles that don't have the FPCM, like my 2007 HHR 2.4L for example. Very exciting for forced air applications. Because the TVS configuration I have built will produce 20 to 22 PSI of boost, this is something I'm definitely going to look into.

 

i doubt that the foot-dragging wheel is distinct on the crank shaft!
this is what will not allow them to swap

 

why don't you just swap the flux capacitor and warp drives??? that should do it....

 

impressive write up! i'd be interested to see this done!