The MegaSquirt Project has experienced explosive growth other the years, with hundreds of new MS installations occurring every week - a phenomenal success! MegaSquirt has been successfully used in all aspects of Internal Combustion engine applications including R&D, Industry, Race, and Research. The MS project has transformed itself from a simple R&D project into a full-featured mature engine control system. To reflect this the support structure has also changed to meet the needs of MegaSquirt Users.
Moving forward, the R&D forums for MegaSquirt project are in a read-only mode - no new forum posts are accepted.
However the forums will remain available for view, they still contain a wealth of information on how MegaSquirt works, how it is installed and used. Feel free to search the forums for information, facts, and overview.While the R&D forum traffic has slowed in recent years, this is not at all a reflection of Megasquirt users, which continue to grow year after year. What has changed is that the method of MegaSquirt support today has rapidly moved to Facebook, this is where the vast majority of interaction is happening now. For those not on Facebook the msextra forums is another place for product support. Finally, for product selection assistance, all of the MegaSquirt vendors are there to help you select a system, along with all of the required pieces to make it complete.
Forum rules
Forum rules
Read the manual to see if your question is answered there before posting. If you have questions about MS1/Extra or MS2/Extra or other non-B&G code configuration or tuning, please post them at http://www.msextra.com The full forum rules are here: Forum Rules, be sure to read them all regularly.
I understand the hi/lo impedance aspect of the current limiting pwm going to the injectors.... but....
What 'real' shift in VE table values (up/dn ?..rough % based on injector size) might be dicernable if tuning on high impedance injectors was done with the limit still set at 75% instead of 100%. Would this in effect, reduce the injection amounts by some measureable amount acrtoss the board? Is this measureable? Calculatable? )sp?
If the PWM is sufficient to open and hole the injectors open, the fuel flows at the full rate. Often 75% is enough for high impedance injectors, under perfect conditions. If the battery voltage falls, the ambient temperaturee falls, etc., there could be problems though.
If the PWM% rate is not sufficient, the injectors might open, then they will close after a time, regardless of the commanded pulse width. So the effect is pulse width dependent, not VE.
However, it would be very noticeable if you were running too little PWM% in most cases. Things like high load, and accel enrichment, and warm-up enrichments would not work very well at all.
Also, note that both the PWM% (essentially the 'effective voltage') and the PWM time threshold (the time at the beginning of the pulse during which PWM is NOT applied) would have to be wrong, and this is unlikely for people who have read the manual. If PWM% is 100% OR PWM time threshold is 25.4+ milliseconds, then no PWM was used at all, and as a result no compensation is needed.
What 'real' shift in VE table values (up/dn ?..rough % based on injector size) might be dicernable if tuning on high impedance injectors was done with the limit still set at 75% instead of 100%. Would this in effect, reduce the injection amounts by some measureable amount acrtoss the board? Is this measureable? Calculatable? )sp?