Recently I had an chance to use a SDS EM2 system - a bit of feedback.
Keep in mind this is an older model so I do not know if it applies to what SDS is currently selling.
- there is no altitude compensation in it
- the primary fuel curve is rpm based with a modifier for engine vacumm
- driving from 3500' to 5900' at Denver then to 700' at Tulsa OK. we were constantly adjusting the fuel curve
- the fuel adjustment is really crude compared to a system that has a 3D fuel map (just about every other system out there).
- on this unit there is no place to add in vacumm advance timing - just retard for boost.
- the timing is rpm based only for NA applications.
The transitions on/off the throttle had to be adjusted using the mixture knob.. We just could not keep up with the different operating conditions.
The owner has used the system for > 15 year so know it quite well.
My opinion: for the cost of a megasquirt ($400 pre-built) and a used laptop ($100 to $150 locally) I would not go the SDS route.
For applications that run at a constant altitude and power setting its ok but that is not what we do when we drive around is it?
Last edited by efi-diy; 09/18/14 08:37 PM.