Found this here

"The Twin Power ignition amplifier incorporates both the CDI and transistor method ignition to provide optimum spark duration and maximum voltage output, resulting in crisper throttle response and a smoother engine powerband. The CDI method, capacity discharge ignition, provides maximum voltage by transferring all stored energy in the capacitor to the ignition coil so that the ignition current can buildup quickly, thus making the Twin Power very effective in the higher revs where a normal spark would tend to diminish. This strong rapid spark prevents the high rpm ignition miss that reduces peak power. The transistorized method generates high voltage by using transistors to cut off current to the coil, thus allowing for a long energy discharge. This longer spark duration allows the Twin Power to improve lower RPM throttle response and torque. The combination of the CDI and the transistor method incorporates two distinct systems into one high performance unit, hence the designation of Twin Power. The Twin Power produces a spark output that is typically 1.5-2.5 stronger than of the stock ignition system and consumes about 35% less power input than other ignition amplifiers. Each compact and attractive Twin power unit is constructed of durable anodized aluminum and sealed to prevent corrosion from moisture. General wiring harnesses are included in each unit to aid in installation and mounting. Vehicle Specific wiring harnesses are also available for certain models to further aid in installations that require intricate integration.(CARB E.O. # D-186-22)"

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Just like most aftermarket ignition systems, unless you have extensive mods or forced induction, you will rarely see any improvements from this mod.

 

On a stock Z I wouldn't really expect any power gains, but you might get a smoother idle and better mileage. I put an MSD ignition on my Buick and it made a big difference, but that was over the factory points ignition, not the nice coil-on-plug ignition the Z has.

 

Agreed. I run one on my GVR4 and it did give me some more tuning head room, but thats a car running big boost.

You really cannot improve on the Z's ignition system short of going to a full standalone (for the sheer control aspect of it, not for the increase in spark intensity)

Adam