Does an Aftermarket PCM still require the use of the ICM?
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I'm upgrading to a standalone sequential FAST system. I'm also going to be using a MSD Digital 6 for ignition, but am keeping the Opti for now. Do I still need to use the ICM, and can I get a different coil now, or does the Opti remaining dictate that? Was thinking that there is a better coil out there, or is the stock replacement MSD really worth keeping?
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It's going to use a single coil, driven by the MSD Digital 6, which will get it's signal from the FAST. The FAST is setup to still use the signal from the opti though. I figured the ICM (Ignition Control Module) is there more for the stock PCM rather than the coil. With the stock PCM, it seems that the MSD box would get the coil trigger from the ICM, but the way it seems, the MSD box will now get the trigger directly from the FAST system, unless I'm missing something. I noticed that Joe Overton was still using the ICM in one picture in the magazine spread even though he's using a standalone GenVII setup.