I currently use a 1227747 with Dual TBI-700 Throttle bodies on a Corvair. I use a V6 DIS using the Harmonic balancer as my trigger. I wanting to upgrade to a newer ECM and have selected the 7427.

I'm switching to a 16197427 PCM. When I setup my 7747 ECM I had to set the Initial spark advance to 60 degrees, Maximum Spark allowed to 75 degrees and Maximum Retard allowed to -75 degrees (offset) to get the DIS to work. (Help provided by Bill on this forum).

My question is; what settings will have to be changed in the 7427 PCM to get the DIS to run the way I have it? I have a drilled HB and changing it would be a challenge at best.

Ted
Anderson, SC

 

You should find that the same changes work with the new PCM, though yo may have to set maximum advance a little higher.

 

Its been so long since I worked with that setup, I honestly don't remember. At first glance that looks pretty close to functional. I remember looking over the calibration for a 3800 FWD engine to get it.

I think it was INITIAL TIMING of 60* (basically tells the PCM the base timing is at 60*).... 70* MAX Retard and -10* Max advance. Basically gives you 10* worth of retard and limits you to 50* max advance, based on the 60* initial setting.

Keep in mind that my values were on a MPFI 3.4 Camaro engine in a S10 Blazer running the 7427 PCM.