MicroSquirt.com read only forum (Jan.15,2018)

I'd like to be able to tune the system for best performance and best milage and be able to switch between the two on the fly.

RauchOffRoad

please read this first;
http://megasquirt.sourceforge.net/extra ... witch.html

yes, you can change fuel maps, but it is generally not useful except for specific applications you are trying to solve. It may help some when changing high altitude.

give us more specifics; do you want to do this with a switch, automatically based on some parameter...... what are you running? MS1 version?, what firmware? etc.

You can change fuel tables based on a switch, or you can set some output based on an engine parameter like rpm and then hook that output to change table automatically instead of a switch.

As Eric explains here:

http://www.msefi.com/viewtopic.php?p=84460&#84460

Switching fuel maps typically is done for gasoline versus LPG or something, since switching fuel maps for one type of fuel is a "carburetorism" that you don't need with a properly tuned EFI setup (the low load part of the tune is set for economy and the high load is tuned for power; trivial with EFI, hard with carbs).

So the real 'switch' is your right foot...

Lance.

I don't have anything right now just doing some research on what I should use either SMT 7 or MS2. I know that there is an optimal fuel a/f ratio for performance and one for milage. With SMT7 you can switch on the fly, i'd like to be able to do that with what ever I choose.

RauchOffRoad,

With MS-II you have a 12x12 AFR table, allowing you to specify the EGO feedback AFR under 144 different operating conditions (assuming you have a wideband controller that can actually measure these AFRs).

In any case, you have a 12 x 12 VE table that can be used to adjust the fuelling (and thus the AFR) under 144 conditions (apart from the EGO feedback).

The lower part of those 12 x 12 tables is for increased economy (high AFR), the upper part for performance (low AFR).

However, before making a choice, you really should read more about tuning (http://www.megasquirt.info/ms2/tune.htm).

Lance.