2gGSX
15+ Year Contributor
- 1,956
- 31
- Feb 15, 2004
-
St. Louis,
Missouri
Log "Air Flow" via ECU+ Head Unit --> MUT-II Logging.
Also, theres a panel under the ECU+ Head Unit that's called "Injector Scaling". Is that where you're compensating for the 550's (and you said this operates via modifying the MAS signal right)?
I can also tell you now that the ECU is pulling one degree timing during the pull because of the intake temperature.
Without the (corrected) airflow data, it's impossible to figure out g/rev and thus what the timing *should* be. My guess though, is that due to the compensation for 550's (-18% airflow), you're being put on a lower load timing map. To get back on the ECU's stock high timing map, you have to exceed 2.1 g/rev of airflow. With that in mind, you'd have to see 34 lbs/min at 6000 RPM, 36.7 at 6500 RPM, and 39.6 at 7000 RPM. On an average Evo 3 setup, you should be able hit 34 lbs/min at 6000 RPM, although the rest is sort of tricky. In effect, you'll be running the stock high timing map until 6000 RPM, after which you would drop to the next highest timing map (1.8 g/rev), which would aim for 19 degrees of timing advance until you let off.
Looking at your log with the 550's, the car's behavior seems to correlate to what I just said fairly closely.
The only real issue that you're going to have with ECU+ it seems is that without huge actual (e.g. before correction) airflow in the upper RPM band, the ECU will drop you into a lower load timing map and try to run more timing. The problem is aggravated proportionately by your injector size. For example, with 650cc injectors you would need 33.4 lbs/min of airflow at 5000 RPM, 36.7 lbs/min at 5500 RPM, 40.1 at 6000, 43.4 at 6500, and 46.7 at 7000 RPM (again, all true airflow). That probably wouldn't happen with an Evo 3, although it would be feasible with a 50 trim turbo or larger.
Edit: you're probably going to TL;DR the above, but at least pay attention to whats below--
BACK TO YOUR QUESTION THOUGH--
I would up boost and watch your timing, and more importantly your knock VERY closely. Without more airflow, you're already getting natural timing advance from falling into a lower timing map. More boost should = more airflow, and I think that this would make things easier to tune.
Also, theres a panel under the ECU+ Head Unit that's called "Injector Scaling". Is that where you're compensating for the 550's (and you said this operates via modifying the MAS signal right)?
I can also tell you now that the ECU is pulling one degree timing during the pull because of the intake temperature.
Without the (corrected) airflow data, it's impossible to figure out g/rev and thus what the timing *should* be. My guess though, is that due to the compensation for 550's (-18% airflow), you're being put on a lower load timing map. To get back on the ECU's stock high timing map, you have to exceed 2.1 g/rev of airflow. With that in mind, you'd have to see 34 lbs/min at 6000 RPM, 36.7 at 6500 RPM, and 39.6 at 7000 RPM. On an average Evo 3 setup, you should be able hit 34 lbs/min at 6000 RPM, although the rest is sort of tricky. In effect, you'll be running the stock high timing map until 6000 RPM, after which you would drop to the next highest timing map (1.8 g/rev), which would aim for 19 degrees of timing advance until you let off.
Looking at your log with the 550's, the car's behavior seems to correlate to what I just said fairly closely.
The only real issue that you're going to have with ECU+ it seems is that without huge actual (e.g. before correction) airflow in the upper RPM band, the ECU will drop you into a lower load timing map and try to run more timing. The problem is aggravated proportionately by your injector size. For example, with 650cc injectors you would need 33.4 lbs/min of airflow at 5000 RPM, 36.7 lbs/min at 5500 RPM, 40.1 at 6000, 43.4 at 6500, and 46.7 at 7000 RPM (again, all true airflow). That probably wouldn't happen with an Evo 3, although it would be feasible with a 50 trim turbo or larger.
Edit: you're probably going to TL;DR the above, but at least pay attention to whats below--
BACK TO YOUR QUESTION THOUGH--
I would up boost and watch your timing, and more importantly your knock VERY closely. Without more airflow, you're already getting natural timing advance from falling into a lower timing map. More boost should = more airflow, and I think that this would make things easier to tune.
