Starting ignition upgrade. Choosing between the MSD DIS-4 PLUS or the MSD Hemi-6 controller. With the MSD blaster coils. Any thoughts? Comments? I know there is a needed harness and adapters for the Hemi-6, not sure about the dis-4 though.

Also have the 10.4mm Taylor Thundervolts and new copper plugs.

 

What is done to the engine that would require an ignition upgrade? The stock set-up is more than adequate.