Originally Posted by
risen
I guess it all depends on how you want to go about installing the MS. I believe that someone on another site was reporting that our HEP's are now supported in the MS code, however I'm not sure what version. So you could get the right software revision and wire the MS up to the HEP. Otherwise, you need to find a way to trigger the MS so it knows the RPM.
It'll be 100x easier to just build yourself an overlay harness and take key-on power from the bulkhead somewhere. I've gone down the route of cutting out everything that isn't necessary and running the MS in it's place. It's a pain unless you really have the time and energy to do it.
As to the integration with the factory stuff, the major considerations is the voltage regulator. We used a '70's mopar VR and wired it up to the alternator, seems to function better than the PM controlled one IMHO.
Another consideration is the cooling fan. We used the fidle output on the megasquirt set it to come on @ 195 above 300 rpm. We had to chain up a relay, because the fidle relay on the relay board couldn't handle the amperage.