Does anyone have experience operating a subie with Variable Valve Timing sensors to read oil pressure (engine load) and then activate solinoids to either retard or advance valve timing via cam rotation?...Thumbs up, or thumbs down?
Geez, that sounds complicated!
Thanks, Carl
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Last I checked none of the major tuners have been able to make the AVCS VVT controls work with standalone engine management. The AVLS is not an issue and can be controlled with a simple GPO that is RPM based.
That said, I have not looked in several months and things change quickly, however I am also not using standalone management anymore unless specifically requested so everything we do gets a stock ECM, and we have no issues controlling AVCS with a stock ECM modded for a Beck.
Thanks, I had a gut feeling it was a potential can of worms!
Carey,
Is there any 'space difficulties' installing an EJ2.5 into your speedsters as opposed to a 2.0 or 2.2 conversion?
none at all
Last I checked none of the major tuners have been able to make the AVCS VVT controls work with standalone engine management. The AVLS is not an issue and can be controlled with a simple GPO that is RPM based.
That said, I have not looked in several months and things change quickly, however I am also not using standalone management anymore unless specifically requested so everything we do gets a stock ECM, and we have no issues controlling AVCS with a stock ECM modded for a Beck.
Megasquirt 3 has VVT settings, but I don't know if/how they work. Or how much extra hardware is required. Last time I read anything about VVT subie swaps they were still just putting bolts in the cams to lock the timing.
Controlling VVT through a standalone can be easy on some motors. The AVLS systems are a simple "on/off" switch that is triggered at a preset RPM. Simply set a GPO (output) to send 12v or ground (whatever is needed by your motor) at a preset RPM and when you hit that RPM the solenoid pulls just as in the stock ECU set-up.
However, if I understand it correctly, the AVCS system uses a series of engine sensors to determine how much hydraulic pressure to send to valves that control the VVT/cam position and not only does the pressure itself vary, the point at which this process is initiated also varies, making it more difficult (or maybe impossible thus far?) to control with standalone.
Specialty Auto-Sports makes replicas with Sub'ru engines, and they seem like upfront guys who might answer your questions.
Carl,
Similar discussion happening on Spyderclub and Larry (Jowdy) is reporting that John @ Outfront has worked out the control of the AVCS with an Australian built standalone ECU. John is a very approachable guy and sounds like he'd be a good contact for this.
