I'm trying to work out the spark control on my engine and have been online with MSD and FAST and not getting what I consider cohesive answers. I'm hopeful one of you can provide an answer or direction on this. The basics, I have the FAST XFI 2.0 system (have had it for over 10 years), I have an early FAST Dual Sync Dist (I've had to modify it in several ways to make it dependable) and I have a MSD Flying Magnet Crank trigger (Hall effect??) mounted and all front drive components have been modified to make up for the crank wheel thickness and an MSD 6A ignition box. My issue is getting all of these items to work together in a sequential system. According to fast since I am not using the crank side of the dual sync I need to jumper that to ground. No Problem, that grounds the discrete crank signal. Do I then connect the leads from the crank trigger to the "Inductive Crank wires into the ECU? This is where things start to get fuzzy.
I will say that I am not opposed to either running the dual sync as it is designed and leaving the Crank Trigger disconnected, Or do I purchase a different distributor that will work with the system? I just want to make sure this is all connected together correctly before firing the engine up.

 

The MSD crank trigger is a 2 wire variable reluctance sensor, hall effect would be a 3 wire sensor. I'm not familiar with the inputs on the Fast but there should be someplace where you set this up in the software. If there are 2 inductive crank wires that's probably where you connect them. There is a proper polarity to the wires, if they are reversed it will cause timing problems. I would think most of this should be in the instructions/wiring diagram.

 

Mid, thanks for the reply. Telling the difference between 2 wire and 3 helps. Now I understand the difference. I've had to dive deep into the instructions for all of the components and between them all found all the information I need. Coincidentally, FAST has the crank trigger issues covered, just had read very closely in the EFI manual. I'm on the right track now.

 

I'm having almost the same issue. When I read the instructions it says to ground 1 of the signals, either the dual sync or crank trigger. Ok, do you ground it on the distributor harness side? Do you take the wire out of the main harness and ground it?

 

To also follow up, I want to run sequential.