Join Date: Jul 2005
Location: Austin Texas
Ferrari Life Posts: 1,833
There are may different curves built into the microplex boxes. There are 3 different programs utilizing the various curves under different conditions built into it to cover all market requirements.
The Base, US and Switzerland (the most conservative).
There is a ground wire attached to either pin 17 for the US, 23 for Switzerland or neither for Base.
It is all in the various Microplex diagnosis materials but they really don't point to it.
There is not a big difference to any of the settings and in fact all of them are very conservative. My 328 is running nearly 11:1 compression with the base curve on California rat urine gasoline and there is no problem with detonation.
I tested it years ago with a Jofatron and there was a max difference of about 4 degrees in some low to mid RPM areas.