The voltage required to fire the plug is determined by the plug gap, electrode condition, cylinder pressure, and A/F mixture, typically 15-30kV for a normally aspirated Street engine. Using a coil capable of 57kV will not raise the voltage at the plug before it fires. It will not produce more power.

The “multiple spark discharge” devices generate a bit more current flow, and induce multiple sparks (up to 3000-3,500 RPM, depending on model) to increase complete fuel burn, but typically beneficial only on power adder setups - forced induction or nitrous. The upgraded models - Digital 6, 7-series - add rev limiters, timing retard, two-steps, and programmable features required by high HP builds, or power adders. Putting a 7A on your engine will not change anything.

For what appears to be a stock engine with a CAI , headers and a catback, the stock ignition should be adequate. The 96/97 single-connector stock coil is supposedly superior to the 93-95 dual-connector coil.

YOU DON'T NEED 57,000 VOLTS. Spray a 200-shot, or add 12# of boost, or open the plugs to 0.100, or run it lean, or bump the compression to 12:1. Probably still wouldn’t require 57,000 volts.

I explained it above.... the voltage is whaterever the laws of physics determine is required to jump the spark plug gap - width of gap, condition of electrodes, cylinder pressure, compression ratio, temperature of charge, A/F ratio, etc.. The voltage builds until the spark can jump the gap, and with a stockish engine, it's probably not more than 20,000 volts, if even that. And if somehow you built an engine that did require 57,000 volts, the 8.5mm plug wires would be inadequate.

Don't fall into the”bigger is always better” numbers trap.

Point of reference..... here's the coil for an NHRA Top Fuel dragster. Max voltage is 45,000

https://www.holley.com/products/igni...SABEgKXT_D_BwE