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Old 07-20-2012, 08:06 PM   #35
arghx7
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Quote:
Originally Posted by SkullWorks View Post
We are working on an AEM solution and similarly we are scoping the Direct injection Port injection, spill valve ETC. to verify factory operation, at this point all I can add to the discussion is that there are clearly some contradictions to how the DI is used compared to some of the early toyota papers.
I think it's definitely been confirmed that simultaneous injection is occurring over 5000rpm under WOT conditions. This was in the service manual and has been logged with ECUtek.

This is a different engine and naturally it's going to be different from a 6 cylinder luxury car. I can't stress enough that if you are comparing your own data with some other source that uses physical units (like actual absolue crank angle degrees) make sure your conversions are done correctly. Duty cycle and ON/OFF inputs are simple enough, but calculating timing can be tricky.

If you are using automated software to calculate the injection timing, you have to figure out the offset between true TDC and the missing tooth of the waveform. It's also more accurate if you look at the CURRENT WAVEFORM not the voltage. Use a current probe that outputs a linear voltage signal proportional to the actual current in the injector. If you hook the scope or whatever equipment you are using up and read the raw voltage, you will pick up a ton of noise.

This will be obvious if you are manually calculating injection timing at discrete points based on visually looking at the waveform. Simple automated software will be thrown off if you have it register an injection event based on some raw voltage threshold. Reverse engineering stuff with a scope is tricky and it's easy to misinterpret the data.
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