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Hello guys.I have to tune a Honda cbr 600rr 07'(rev limiter at 13400 RPM).I don't understand completely how I can adjust injection timing.Intake valves open at 27 deg BTDC and close 38 deg ATDC(New camshafts for 6 deg earlier opening-closing of the valves).I use "End of injection".So as fas as I understand the theory I have to enter at 1000RPM 218 deg(180 deg intake stroke +38 deg for valve) but I know that it's not correct.How does exactly injection timing depends on RPM and on load?Should I start with 218 deg at 1000RMP and increase/decrease injection timing as RPM increase?I have read that I can adjust injection timing and look for the richest lambda at each RPM and load.Can anyone help me with that?
Typically when tuning injection timing you won't have knowledge of the actual valve timing events. My personal technique is to use the lambda and torque values on the dyno and watch these while adjusting the EOI angle. If you hold the engine in steady state on the dyno and advance or retard the timing by say 20 degrees at a time, you can watch the effect on both lambda and torque. As you move in the right direction you will find the lambda moves richer as the same volume of fuel is being injected but it's being injected at a point where it can more easily mix with the air and hence combust properly.
Once you have found the lambda plateaus you can then remove fuel from your main fuel map and this will benefit fuel economy and may show a small increase in engine torque. As you move through the map you will see a pattern emerge of the preferred injection timing and should be able to follow this through the map. Understand that the sort of gains you are likely to see from injection timing are often small though.
One aspect to keep in mind is that if you really want to take maximum advantage of injection timing, you will need to size your injectors so that your maximum injector duty cycle only reaches perhaps 50-60%. If you are seeing IDC reach 80-90% it doesn't really matter what the EOI angle is as the injectors are open almost all of the engine cycle anyway.
There is a webinar on the subject here: https://www.hpacademy.com/previous-webinars/injector-timing-on-the-motec-m1/
Nice Andre thanks for the explanation.I will watch that webinar