and do you have scope from running engine ?
Has this issue with the dyno plot been resolved? I’m seeing the same behavior in 3.602 beta.
If torque is Nm and power is HP, I would expect:
257 Nm * 0.7 lb-ft/Nm / 5252 RPM * 6908 RPM = 236.6 HP
instead of 187 HP.
Hello!
Do you know when the easy Setup wil included to the software?
@Jadzwin_ECUMASTER back to this. I was hoping it would get resolved if I just waited. However, with the latest version 62 firmware, interpolated fuel cut rev limiter still does not work for me. Different car too. There is only a hard cut. When I go back to version 53, it works right.
If this were working at all, you’d see lambda go lean with 1.5 seconds, regardless of how much residual fuel there may be.
What is easy setup ?
I will take a look again for the issue. I analyzed a log and there is injectors cut.
What engine is it ? Was the previous engine the same ?
Previous was a Toyota 2ZR, this one is a Toyota 2AR. Both port injected.
We wrote about a time based boost target function like the AMS 2000.
For example: i start with 5 psi, after 2 second 10 psi and finaly after 8 second 30 psi.
The possibility, depending on the track conditions, to adjust the boost pressure upwards and downwards at different times.
There is a boost correction table in Timer section.
The timer can start as soon as the Launch control is finished and you can adjust the boost as a function of time.
It is quite the same as you propose, just use relatvie values not absolute
I performed tests on a Lexus IS200 and also tested your calibration on the bench.
Everything is working well.
Below is the scope capture at full throttle, 3700 RPM, during fuel cut.
I also experimented with the injection angle, and it clearly influences the smoothness of the cut.
Next, we tested per-injector fuel cut. There was a small overshoot at the beginning, but overall the rev limiter response was very fast and clean. The engine was unloaded during the test; under load the effect is much better.
The best results were achieved with spark cut — it is the fastest method and provides a very stable rev limiter.
If spark cut cannot be used to control the rev limiter, I recommend using per-cylinder fuel cut.
For some reason, the standard strategy does not work properly with your engine.
I suspect this may be related to the injection angle and residual fuel. When the cut occurs, previous injection events may still be in progress and will complete afterward, which can cause the observed behavior.
One thing you can try is retarding the ignition during the rev limiter, for example by about 15°, since the engine will be operating in a lean condition. You can also experiment further with the injection angle.
If this approach does not help, we can work on improving the standard fuel cut strategy.
Thanks for looking into this. Glad to see fuel cut % has been added back to the log for rev limiter.
Here’s a log with FW 3.053. Note a couple things -
- lambda goes lean as fuel cut % increases
- interpolation begins immediately on activation of limiter
- RPM is smooth!
- This engine seems to stop accelerating at about 50% fuel cut, and therefore does not reach target - this is fine!
Now here’s a log with FW 3.062.
- Limiter goes active 400rpm before target.
- Fuel cut % does not increase until we are within 100rpm of target.
- Nearly immediately goes to and flattens at 38% fuel cut.
- RPM bounces.
I understand what the problem is and why we cannot reach an agreement.
In version 3.057, the soft rev limiter algorithm was completely rewritten, and its operating principle was changed in order to achieve a simple-to-configure and very fast rev limiter (especially when using spark cut).
Additionally, this mechanism is also used in Launch Control and Rolling Start.
During our internal tests, we did not observe any issues when using fuel cut, but as we can see, in your engine it works worse than the previous strategy.
I have an idea for a modification of the fuel-based strategy, but unfortunately in our test cars the current implementation works correctly, so we cannot reproduce the issue. If you have the possibility to test it, I can introduce a modification for testing within 2–3 days.
In the meantime, you can try per-injector cut, which works very well.
To summarize, this is not a bug—it is a completely new strategy, which, as we can see, still requires some further refinement.
I understand the situation and appreciate your attention to it. I am happy to test an update. The last couple cars I sent home with V3 firmware got per cylinder fuel cut which does work well.
Here is how I have found partial fuel cut on these engines works best. RPM Limiter Error generally ends around -200rpm depending on load.
