My SDS tunning manual and microprocessor show inputs for "RPM IGN" and "RET/LOAD". I assume that they set timing advance/retard. I further assume that the "RET/LOAD" sets the ignition timing for various loads of vacuum or boost. I also assume that the "RPM IGN" sets timing advance/retard at various rpms. So, are these settings to be additive, or is there to be a selection of one over the other? The manual does NOT explain what they are nor how they interact. Any help would be appreciated. Bill Spruill

Hi,

the values are additve, set the base curve, maybe 10 at idle to 30 degrees at 3000, than retard the ign. over boost, depanding on your engine spec. For example at 1 bar 20 degrees back, you have to put 20 retard at 14,7 psi. Of cource in a curve not this value alone

Ralf