assane wrote: ↑Thu Feb 04, 2021 9:18 am
I have a car in gasoline with 1.5 bar boost. I would like to install 0.8 bar boost gas for touring. I thought that if there is 2x map and ignition in the tuner studio, why not introduce the double boost setting function? I can do as Chris Wolfson says above, no problem but it would be nice to be able to control this lower boost. It is mainly about the efficiency of the evaporator and gas injectors. The next thing is, as the previous speaker mentioned, let someone drive this car is best on the weaker map for safety.
Thank you. It would appear that you only want two peak boost levels, and control separately within those two levels. As already stated, one fuel table will handle both boost levels correctly, fueling properly at any boost level on either boost table. Therefore, you are only wanting multiple boost tables, and there are various solutions for this, with one already stated. There are other solutions, such as Chris' for a "valet" mode (special boost table not needed), and load a track tune on those days you are racing at either boost level. It takes less than a minute. Options such as this can get you going with full control until firmware solutions are considered for Speeduino.
Next, you originally wanted "polarity function inverted", which I am guessing means you want reversed operation, with boost rising with decreased PWM duty cycle? That's possible, but unusual, as hardware is typically set-up to provide minimum boost if control fails. It may be simpler and safer to alter the hardware setup to allow default bleed, so a failed valve or wire connection will not force over-boost. This is the primary reason an 'inverting' option is usually avoided. One easy alternative is to simply invert the values in your boost table, with max DC at low-load, but again not recommended. Does that help?