No idea.
I can only speak to what I have personally done. I don't know crap about tuning a Supra. I do know how to tune Toyota trucks and there are limits to different approaches. I might be able to tune 668s just fine, but I have not done it so I cannot tell someone it works.
I can tell you that the MAF Elimination mode of the MAP-ECU2 totally does not work on Toyota trucks, but it works very well on the Supra. Don't ask me why because I can't tell you....
There are other issues with jacking the MAF signal to far off also. The more you reduce it to dial in BIG injectors causes the ECUs load calculations to be really off. This has a few side effects. One is that it will want to advance the ignition timing significantly which is not always good on an engine covertred to forced induction. It also causes the auto trans to shift different;y. The 1GR uses a load calculation to alter how it shifts, not so much when, but how. We discovered this with the X-1.
The way the X-1 was setup is that the MAF flow would be feed back to the ECU to mirror the flow limits of a stock engine while the X-1 took full control. The ECU thought it was still running a stock engine and was kept happy while the X-1 took over the hard work. The problem appeared with the auto trans was doing the slide slip bump shifts because of the load control on it was for a stock N/A engine. So, this was changed to allow the full MAF signal to go through and the trans started shifting much better and crisper without going into the rev limiter as much. That cause other things that needed to be done. The ignition timing tables had to be redone to compensate for the ECU pulling more timing and so on.
With these newer engine control systems we really need to control the ignition after the ECU and same with the injectors. This is very different than most of the piggy backs on the market. The Unichip is still tuning fuel by jacking the MAF sensor, so is the MAP-ECU2. AEM has a product that adjusts the injectors directly. Now for ignition, we really need to adjust that on the back side of the ECU also. The MAP-ECU2 does this by adjusting the signal to the ignitors and so does the X-1. Now AEM and unichip are jacking with the signal from the crank position sensor on the front side of the ECU. This has side effects of screwing up the VVTi and injector timing and some other things.
Anyway, what I am getting at here is minor tweaks to the signals works, but go to far and you have unwanted side effects and so on. There are pros and cons and limits to every approach.
G
